| 1 | macro_rules! int_impl { |
| 2 | ( |
| 3 | Self = $SelfT:ty, |
| 4 | ActualT = $ActualT:ident, |
| 5 | UnsignedT = $UnsignedT:ty, |
| 6 | |
| 7 | // These are all for use *only* in doc comments. |
| 8 | // As such, they're all passed as literals -- passing them as a string |
| 9 | // literal is fine if they need to be multiple code tokens. |
| 10 | // In non-comments, use the associated constants rather than these. |
| 11 | BITS = $BITS:literal, |
| 12 | BITS_MINUS_ONE = $BITS_MINUS_ONE:literal, |
| 13 | Min = $Min:literal, |
| 14 | Max = $Max:literal, |
| 15 | rot = $rot:literal, |
| 16 | rot_op = $rot_op:literal, |
| 17 | rot_result = $rot_result:literal, |
| 18 | swap_op = $swap_op:literal, |
| 19 | swapped = $swapped:literal, |
| 20 | reversed = $reversed:literal, |
| 21 | le_bytes = $le_bytes:literal, |
| 22 | be_bytes = $be_bytes:literal, |
| 23 | to_xe_bytes_doc = $to_xe_bytes_doc:expr, |
| 24 | from_xe_bytes_doc = $from_xe_bytes_doc:expr, |
| 25 | bound_condition = $bound_condition:literal, |
| 26 | ) => { |
| 27 | /// The smallest value that can be represented by this integer type |
| 28 | #[doc = concat!("(−2<sup>" , $BITS_MINUS_ONE, "</sup>" , $bound_condition, ")." )] |
| 29 | /// |
| 30 | /// # Examples |
| 31 | /// |
| 32 | /// ``` |
| 33 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN, " , stringify!($Min), ");" )] |
| 34 | /// ``` |
| 35 | #[stable(feature = "assoc_int_consts" , since = "1.43.0" )] |
| 36 | pub const MIN: Self = !Self::MAX; |
| 37 | |
| 38 | /// The largest value that can be represented by this integer type |
| 39 | #[doc = concat!("(2<sup>" , $BITS_MINUS_ONE, "</sup> − 1" , $bound_condition, ")." )] |
| 40 | /// |
| 41 | /// # Examples |
| 42 | /// |
| 43 | /// ``` |
| 44 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX, " , stringify!($Max), ");" )] |
| 45 | /// ``` |
| 46 | #[stable(feature = "assoc_int_consts" , since = "1.43.0" )] |
| 47 | pub const MAX: Self = (<$UnsignedT>::MAX >> 1) as Self; |
| 48 | |
| 49 | /// The size of this integer type in bits. |
| 50 | /// |
| 51 | /// # Examples |
| 52 | /// |
| 53 | /// ``` |
| 54 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::BITS, " , stringify!($BITS), ");" )] |
| 55 | /// ``` |
| 56 | #[stable(feature = "int_bits_const" , since = "1.53.0" )] |
| 57 | pub const BITS: u32 = <$UnsignedT>::BITS; |
| 58 | |
| 59 | /// Returns the number of ones in the binary representation of `self`. |
| 60 | /// |
| 61 | /// # Examples |
| 62 | /// |
| 63 | /// ``` |
| 64 | #[doc = concat!("let n = 0b100_0000" , stringify!($SelfT), ";" )] |
| 65 | /// |
| 66 | /// assert_eq!(n.count_ones(), 1); |
| 67 | /// ``` |
| 68 | /// |
| 69 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 70 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 71 | #[doc(alias = "popcount" )] |
| 72 | #[doc(alias = "popcnt" )] |
| 73 | #[must_use = "this returns the result of the operation, \ |
| 74 | without modifying the original" ] |
| 75 | #[inline(always)] |
| 76 | pub const fn count_ones(self) -> u32 { (self as $UnsignedT).count_ones() } |
| 77 | |
| 78 | /// Returns the number of zeros in the binary representation of `self`. |
| 79 | /// |
| 80 | /// # Examples |
| 81 | /// |
| 82 | /// ``` |
| 83 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX.count_zeros(), 1);" )] |
| 84 | /// ``` |
| 85 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 86 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 87 | #[must_use = "this returns the result of the operation, \ |
| 88 | without modifying the original" ] |
| 89 | #[inline(always)] |
| 90 | pub const fn count_zeros(self) -> u32 { |
| 91 | (!self).count_ones() |
| 92 | } |
| 93 | |
| 94 | /// Returns the number of leading zeros in the binary representation of `self`. |
| 95 | /// |
| 96 | /// Depending on what you're doing with the value, you might also be interested in the |
| 97 | /// [`ilog2`] function which returns a consistent number, even if the type widens. |
| 98 | /// |
| 99 | /// # Examples |
| 100 | /// |
| 101 | /// ``` |
| 102 | #[doc = concat!("let n = -1" , stringify!($SelfT), ";" )] |
| 103 | /// |
| 104 | /// assert_eq!(n.leading_zeros(), 0); |
| 105 | /// ``` |
| 106 | #[doc = concat!("[`ilog2`]: " , stringify!($SelfT), "::ilog2" )] |
| 107 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 108 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 109 | #[must_use = "this returns the result of the operation, \ |
| 110 | without modifying the original" ] |
| 111 | #[inline(always)] |
| 112 | pub const fn leading_zeros(self) -> u32 { |
| 113 | (self as $UnsignedT).leading_zeros() |
| 114 | } |
| 115 | |
| 116 | /// Returns the number of trailing zeros in the binary representation of `self`. |
| 117 | /// |
| 118 | /// # Examples |
| 119 | /// |
| 120 | /// ``` |
| 121 | #[doc = concat!("let n = -4" , stringify!($SelfT), ";" )] |
| 122 | /// |
| 123 | /// assert_eq!(n.trailing_zeros(), 2); |
| 124 | /// ``` |
| 125 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 126 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 127 | #[must_use = "this returns the result of the operation, \ |
| 128 | without modifying the original" ] |
| 129 | #[inline(always)] |
| 130 | pub const fn trailing_zeros(self) -> u32 { |
| 131 | (self as $UnsignedT).trailing_zeros() |
| 132 | } |
| 133 | |
| 134 | /// Returns the number of leading ones in the binary representation of `self`. |
| 135 | /// |
| 136 | /// # Examples |
| 137 | /// |
| 138 | /// ``` |
| 139 | #[doc = concat!("let n = -1" , stringify!($SelfT), ";" )] |
| 140 | /// |
| 141 | #[doc = concat!("assert_eq!(n.leading_ones(), " , stringify!($BITS), ");" )] |
| 142 | /// ``` |
| 143 | #[stable(feature = "leading_trailing_ones" , since = "1.46.0" )] |
| 144 | #[rustc_const_stable(feature = "leading_trailing_ones" , since = "1.46.0" )] |
| 145 | #[must_use = "this returns the result of the operation, \ |
| 146 | without modifying the original" ] |
| 147 | #[inline(always)] |
| 148 | pub const fn leading_ones(self) -> u32 { |
| 149 | (self as $UnsignedT).leading_ones() |
| 150 | } |
| 151 | |
| 152 | /// Returns the number of trailing ones in the binary representation of `self`. |
| 153 | /// |
| 154 | /// # Examples |
| 155 | /// |
| 156 | /// ``` |
| 157 | #[doc = concat!("let n = 3" , stringify!($SelfT), ";" )] |
| 158 | /// |
| 159 | /// assert_eq!(n.trailing_ones(), 2); |
| 160 | /// ``` |
| 161 | #[stable(feature = "leading_trailing_ones" , since = "1.46.0" )] |
| 162 | #[rustc_const_stable(feature = "leading_trailing_ones" , since = "1.46.0" )] |
| 163 | #[must_use = "this returns the result of the operation, \ |
| 164 | without modifying the original" ] |
| 165 | #[inline(always)] |
| 166 | pub const fn trailing_ones(self) -> u32 { |
| 167 | (self as $UnsignedT).trailing_ones() |
| 168 | } |
| 169 | |
| 170 | /// Returns `self` with only the most significant bit set, or `0` if |
| 171 | /// the input is `0`. |
| 172 | /// |
| 173 | /// # Examples |
| 174 | /// |
| 175 | /// ``` |
| 176 | /// #![feature(isolate_most_least_significant_one)] |
| 177 | /// |
| 178 | #[doc = concat!("let n: " , stringify!($SelfT), " = 0b_01100100;" )] |
| 179 | /// |
| 180 | /// assert_eq!(n.isolate_highest_one(), 0b_01000000); |
| 181 | #[doc = concat!("assert_eq!(0_" , stringify!($SelfT), ".isolate_highest_one(), 0);" )] |
| 182 | /// ``` |
| 183 | #[unstable(feature = "isolate_most_least_significant_one" , issue = "136909" )] |
| 184 | #[must_use = "this returns the result of the operation, \ |
| 185 | without modifying the original" ] |
| 186 | #[inline(always)] |
| 187 | pub const fn isolate_highest_one(self) -> Self { |
| 188 | self & (((1 as $SelfT) << (<$SelfT>::BITS - 1)).wrapping_shr(self.leading_zeros())) |
| 189 | } |
| 190 | |
| 191 | /// Returns `self` with only the least significant bit set, or `0` if |
| 192 | /// the input is `0`. |
| 193 | /// |
| 194 | /// # Examples |
| 195 | /// |
| 196 | /// ``` |
| 197 | /// #![feature(isolate_most_least_significant_one)] |
| 198 | /// |
| 199 | #[doc = concat!("let n: " , stringify!($SelfT), " = 0b_01100100;" )] |
| 200 | /// |
| 201 | /// assert_eq!(n.isolate_lowest_one(), 0b_00000100); |
| 202 | #[doc = concat!("assert_eq!(0_" , stringify!($SelfT), ".isolate_lowest_one(), 0);" )] |
| 203 | /// ``` |
| 204 | #[unstable(feature = "isolate_most_least_significant_one" , issue = "136909" )] |
| 205 | #[must_use = "this returns the result of the operation, \ |
| 206 | without modifying the original" ] |
| 207 | #[inline(always)] |
| 208 | pub const fn isolate_lowest_one(self) -> Self { |
| 209 | self & self.wrapping_neg() |
| 210 | } |
| 211 | |
| 212 | /// Returns the index of the highest bit set to one in `self`, or `None` |
| 213 | /// if `self` is `0`. |
| 214 | /// |
| 215 | /// # Examples |
| 216 | /// |
| 217 | /// ``` |
| 218 | /// #![feature(int_lowest_highest_one)] |
| 219 | /// |
| 220 | #[doc = concat!("assert_eq!(0b0_" , stringify!($SelfT), ".highest_one(), None);" )] |
| 221 | #[doc = concat!("assert_eq!(0b1_" , stringify!($SelfT), ".highest_one(), Some(0));" )] |
| 222 | #[doc = concat!("assert_eq!(0b1_0000_" , stringify!($SelfT), ".highest_one(), Some(4));" )] |
| 223 | #[doc = concat!("assert_eq!(0b1_1111_" , stringify!($SelfT), ".highest_one(), Some(4));" )] |
| 224 | /// ``` |
| 225 | #[unstable(feature = "int_lowest_highest_one" , issue = "145203" )] |
| 226 | #[must_use = "this returns the result of the operation, \ |
| 227 | without modifying the original" ] |
| 228 | #[inline(always)] |
| 229 | pub const fn highest_one(self) -> Option<u32> { |
| 230 | (self as $UnsignedT).highest_one() |
| 231 | } |
| 232 | |
| 233 | /// Returns the index of the lowest bit set to one in `self`, or `None` |
| 234 | /// if `self` is `0`. |
| 235 | /// |
| 236 | /// # Examples |
| 237 | /// |
| 238 | /// ``` |
| 239 | /// #![feature(int_lowest_highest_one)] |
| 240 | /// |
| 241 | #[doc = concat!("assert_eq!(0b0_" , stringify!($SelfT), ".lowest_one(), None);" )] |
| 242 | #[doc = concat!("assert_eq!(0b1_" , stringify!($SelfT), ".lowest_one(), Some(0));" )] |
| 243 | #[doc = concat!("assert_eq!(0b1_0000_" , stringify!($SelfT), ".lowest_one(), Some(4));" )] |
| 244 | #[doc = concat!("assert_eq!(0b1_1111_" , stringify!($SelfT), ".lowest_one(), Some(0));" )] |
| 245 | /// ``` |
| 246 | #[unstable(feature = "int_lowest_highest_one" , issue = "145203" )] |
| 247 | #[must_use = "this returns the result of the operation, \ |
| 248 | without modifying the original" ] |
| 249 | #[inline(always)] |
| 250 | pub const fn lowest_one(self) -> Option<u32> { |
| 251 | (self as $UnsignedT).lowest_one() |
| 252 | } |
| 253 | |
| 254 | /// Returns the bit pattern of `self` reinterpreted as an unsigned integer of the same size. |
| 255 | /// |
| 256 | /// This produces the same result as an `as` cast, but ensures that the bit-width remains |
| 257 | /// the same. |
| 258 | /// |
| 259 | /// # Examples |
| 260 | /// |
| 261 | /// ``` |
| 262 | #[doc = concat!("let n = -1" , stringify!($SelfT), ";" )] |
| 263 | /// |
| 264 | #[doc = concat!("assert_eq!(n.cast_unsigned(), " , stringify!($UnsignedT), "::MAX);" )] |
| 265 | /// ``` |
| 266 | #[stable(feature = "integer_sign_cast" , since = "1.87.0" )] |
| 267 | #[rustc_const_stable(feature = "integer_sign_cast" , since = "1.87.0" )] |
| 268 | #[must_use = "this returns the result of the operation, \ |
| 269 | without modifying the original" ] |
| 270 | #[inline(always)] |
| 271 | pub const fn cast_unsigned(self) -> $UnsignedT { |
| 272 | self as $UnsignedT |
| 273 | } |
| 274 | |
| 275 | /// Shifts the bits to the left by a specified amount, `n`, |
| 276 | /// wrapping the truncated bits to the end of the resulting integer. |
| 277 | /// |
| 278 | /// `rotate_left(n)` is equivalent to applying `rotate_left(1)` a total of `n` times. In |
| 279 | /// particular, a rotation by the number of bits in `self` returns the input value |
| 280 | /// unchanged. |
| 281 | /// |
| 282 | /// Please note this isn't the same operation as the `<<` shifting operator! |
| 283 | /// |
| 284 | /// # Examples |
| 285 | /// |
| 286 | /// ``` |
| 287 | #[doc = concat!("let n = " , $rot_op, stringify!($SelfT), ";" )] |
| 288 | #[doc = concat!("let m = " , $rot_result, ";" )] |
| 289 | /// |
| 290 | #[doc = concat!("assert_eq!(n.rotate_left(" , $rot, "), m);" )] |
| 291 | #[doc = concat!("assert_eq!(n.rotate_left(1024), n);" )] |
| 292 | /// ``` |
| 293 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 294 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 295 | #[must_use = "this returns the result of the operation, \ |
| 296 | without modifying the original" ] |
| 297 | #[inline(always)] |
| 298 | pub const fn rotate_left(self, n: u32) -> Self { |
| 299 | (self as $UnsignedT).rotate_left(n) as Self |
| 300 | } |
| 301 | |
| 302 | /// Shifts the bits to the right by a specified amount, `n`, |
| 303 | /// wrapping the truncated bits to the beginning of the resulting |
| 304 | /// integer. |
| 305 | /// |
| 306 | /// `rotate_right(n)` is equivalent to applying `rotate_right(1)` a total of `n` times. In |
| 307 | /// particular, a rotation by the number of bits in `self` returns the input value |
| 308 | /// unchanged. |
| 309 | /// |
| 310 | /// Please note this isn't the same operation as the `>>` shifting operator! |
| 311 | /// |
| 312 | /// # Examples |
| 313 | /// |
| 314 | /// ``` |
| 315 | #[doc = concat!("let n = " , $rot_result, stringify!($SelfT), ";" )] |
| 316 | #[doc = concat!("let m = " , $rot_op, ";" )] |
| 317 | /// |
| 318 | #[doc = concat!("assert_eq!(n.rotate_right(" , $rot, "), m);" )] |
| 319 | #[doc = concat!("assert_eq!(n.rotate_right(1024), n);" )] |
| 320 | /// ``` |
| 321 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 322 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 323 | #[must_use = "this returns the result of the operation, \ |
| 324 | without modifying the original" ] |
| 325 | #[inline(always)] |
| 326 | pub const fn rotate_right(self, n: u32) -> Self { |
| 327 | (self as $UnsignedT).rotate_right(n) as Self |
| 328 | } |
| 329 | |
| 330 | /// Reverses the byte order of the integer. |
| 331 | /// |
| 332 | /// # Examples |
| 333 | /// |
| 334 | /// ``` |
| 335 | #[doc = concat!("let n = " , $swap_op, stringify!($SelfT), ";" )] |
| 336 | /// |
| 337 | /// let m = n.swap_bytes(); |
| 338 | /// |
| 339 | #[doc = concat!("assert_eq!(m, " , $swapped, ");" )] |
| 340 | /// ``` |
| 341 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 342 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 343 | #[must_use = "this returns the result of the operation, \ |
| 344 | without modifying the original" ] |
| 345 | #[inline(always)] |
| 346 | pub const fn swap_bytes(self) -> Self { |
| 347 | (self as $UnsignedT).swap_bytes() as Self |
| 348 | } |
| 349 | |
| 350 | /// Reverses the order of bits in the integer. The least significant bit becomes the most significant bit, |
| 351 | /// second least-significant bit becomes second most-significant bit, etc. |
| 352 | /// |
| 353 | /// # Examples |
| 354 | /// |
| 355 | /// ``` |
| 356 | #[doc = concat!("let n = " , $swap_op, stringify!($SelfT), ";" )] |
| 357 | /// let m = n.reverse_bits(); |
| 358 | /// |
| 359 | #[doc = concat!("assert_eq!(m, " , $reversed, ");" )] |
| 360 | #[doc = concat!("assert_eq!(0, 0" , stringify!($SelfT), ".reverse_bits());" )] |
| 361 | /// ``` |
| 362 | #[stable(feature = "reverse_bits" , since = "1.37.0" )] |
| 363 | #[rustc_const_stable(feature = "reverse_bits" , since = "1.37.0" )] |
| 364 | #[must_use = "this returns the result of the operation, \ |
| 365 | without modifying the original" ] |
| 366 | #[inline(always)] |
| 367 | pub const fn reverse_bits(self) -> Self { |
| 368 | (self as $UnsignedT).reverse_bits() as Self |
| 369 | } |
| 370 | |
| 371 | /// Converts an integer from big endian to the target's endianness. |
| 372 | /// |
| 373 | /// On big endian this is a no-op. On little endian the bytes are swapped. |
| 374 | /// |
| 375 | /// See also [from_be_bytes()](Self::from_be_bytes). |
| 376 | /// |
| 377 | /// # Examples |
| 378 | /// |
| 379 | /// ``` |
| 380 | #[doc = concat!("let n = 0x1A" , stringify!($SelfT), ";" )] |
| 381 | /// |
| 382 | /// if cfg!(target_endian = "big") { |
| 383 | #[doc = concat!(" assert_eq!(" , stringify!($SelfT), "::from_be(n), n)" )] |
| 384 | /// } else { |
| 385 | #[doc = concat!(" assert_eq!(" , stringify!($SelfT), "::from_be(n), n.swap_bytes())" )] |
| 386 | /// } |
| 387 | /// ``` |
| 388 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 389 | #[rustc_const_stable(feature = "const_int_conversions" , since = "1.32.0" )] |
| 390 | #[must_use] |
| 391 | #[inline] |
| 392 | pub const fn from_be(x: Self) -> Self { |
| 393 | #[cfg(target_endian = "big" )] |
| 394 | { |
| 395 | x |
| 396 | } |
| 397 | #[cfg(not(target_endian = "big" ))] |
| 398 | { |
| 399 | x.swap_bytes() |
| 400 | } |
| 401 | } |
| 402 | |
| 403 | /// Converts an integer from little endian to the target's endianness. |
| 404 | /// |
| 405 | /// On little endian this is a no-op. On big endian the bytes are swapped. |
| 406 | /// |
| 407 | /// See also [from_le_bytes()](Self::from_le_bytes). |
| 408 | /// |
| 409 | /// # Examples |
| 410 | /// |
| 411 | /// ``` |
| 412 | #[doc = concat!("let n = 0x1A" , stringify!($SelfT), ";" )] |
| 413 | /// |
| 414 | /// if cfg!(target_endian = "little") { |
| 415 | #[doc = concat!(" assert_eq!(" , stringify!($SelfT), "::from_le(n), n)" )] |
| 416 | /// } else { |
| 417 | #[doc = concat!(" assert_eq!(" , stringify!($SelfT), "::from_le(n), n.swap_bytes())" )] |
| 418 | /// } |
| 419 | /// ``` |
| 420 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 421 | #[rustc_const_stable(feature = "const_int_conversions" , since = "1.32.0" )] |
| 422 | #[must_use] |
| 423 | #[inline] |
| 424 | pub const fn from_le(x: Self) -> Self { |
| 425 | #[cfg(target_endian = "little" )] |
| 426 | { |
| 427 | x |
| 428 | } |
| 429 | #[cfg(not(target_endian = "little" ))] |
| 430 | { |
| 431 | x.swap_bytes() |
| 432 | } |
| 433 | } |
| 434 | |
| 435 | /// Swaps bytes of `self` on little endian targets. |
| 436 | /// |
| 437 | /// On big endian this is a no-op. |
| 438 | /// |
| 439 | /// The returned value has the same type as `self`, and will be interpreted |
| 440 | /// as (a potentially different) value of a native-endian |
| 441 | #[doc = concat!("`" , stringify!($SelfT), "`." )] |
| 442 | /// |
| 443 | /// See [`to_be_bytes()`](Self::to_be_bytes) for a type-safe alternative. |
| 444 | /// |
| 445 | /// # Examples |
| 446 | /// |
| 447 | /// ``` |
| 448 | #[doc = concat!("let n = 0x1A" , stringify!($SelfT), ";" )] |
| 449 | /// |
| 450 | /// if cfg!(target_endian = "big") { |
| 451 | /// assert_eq!(n.to_be(), n) |
| 452 | /// } else { |
| 453 | /// assert_eq!(n.to_be(), n.swap_bytes()) |
| 454 | /// } |
| 455 | /// ``` |
| 456 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 457 | #[rustc_const_stable(feature = "const_int_conversions" , since = "1.32.0" )] |
| 458 | #[must_use = "this returns the result of the operation, \ |
| 459 | without modifying the original" ] |
| 460 | #[inline] |
| 461 | pub const fn to_be(self) -> Self { // or not to be? |
| 462 | #[cfg(target_endian = "big" )] |
| 463 | { |
| 464 | self |
| 465 | } |
| 466 | #[cfg(not(target_endian = "big" ))] |
| 467 | { |
| 468 | self.swap_bytes() |
| 469 | } |
| 470 | } |
| 471 | |
| 472 | /// Swaps bytes of `self` on big endian targets. |
| 473 | /// |
| 474 | /// On little endian this is a no-op. |
| 475 | /// |
| 476 | /// The returned value has the same type as `self`, and will be interpreted |
| 477 | /// as (a potentially different) value of a native-endian |
| 478 | #[doc = concat!("`" , stringify!($SelfT), "`." )] |
| 479 | /// |
| 480 | /// See [`to_le_bytes()`](Self::to_le_bytes) for a type-safe alternative. |
| 481 | /// |
| 482 | /// # Examples |
| 483 | /// |
| 484 | /// ``` |
| 485 | #[doc = concat!("let n = 0x1A" , stringify!($SelfT), ";" )] |
| 486 | /// |
| 487 | /// if cfg!(target_endian = "little") { |
| 488 | /// assert_eq!(n.to_le(), n) |
| 489 | /// } else { |
| 490 | /// assert_eq!(n.to_le(), n.swap_bytes()) |
| 491 | /// } |
| 492 | /// ``` |
| 493 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 494 | #[rustc_const_stable(feature = "const_int_conversions" , since = "1.32.0" )] |
| 495 | #[must_use = "this returns the result of the operation, \ |
| 496 | without modifying the original" ] |
| 497 | #[inline] |
| 498 | pub const fn to_le(self) -> Self { |
| 499 | #[cfg(target_endian = "little" )] |
| 500 | { |
| 501 | self |
| 502 | } |
| 503 | #[cfg(not(target_endian = "little" ))] |
| 504 | { |
| 505 | self.swap_bytes() |
| 506 | } |
| 507 | } |
| 508 | |
| 509 | /// Checked integer addition. Computes `self + rhs`, returning `None` |
| 510 | /// if overflow occurred. |
| 511 | /// |
| 512 | /// # Examples |
| 513 | /// |
| 514 | /// ``` |
| 515 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MAX - 2).checked_add(1), Some(" , stringify!($SelfT), "::MAX - 1));" )] |
| 516 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MAX - 2).checked_add(3), None);" )] |
| 517 | /// ``` |
| 518 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 519 | #[rustc_const_stable(feature = "const_checked_int_methods" , since = "1.47.0" )] |
| 520 | #[must_use = "this returns the result of the operation, \ |
| 521 | without modifying the original" ] |
| 522 | #[inline] |
| 523 | pub const fn checked_add(self, rhs: Self) -> Option<Self> { |
| 524 | let (a, b) = self.overflowing_add(rhs); |
| 525 | if intrinsics::unlikely(b) { None } else { Some(a) } |
| 526 | } |
| 527 | |
| 528 | /// Strict integer addition. Computes `self + rhs`, panicking |
| 529 | /// if overflow occurred. |
| 530 | /// |
| 531 | /// # Panics |
| 532 | /// |
| 533 | /// ## Overflow behavior |
| 534 | /// |
| 535 | /// This function will always panic on overflow, regardless of whether overflow checks are enabled. |
| 536 | /// |
| 537 | /// # Examples |
| 538 | /// |
| 539 | /// ``` |
| 540 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MAX - 2).strict_add(1), " , stringify!($SelfT), "::MAX - 1);" )] |
| 541 | /// ``` |
| 542 | /// |
| 543 | /// The following panics because of overflow: |
| 544 | /// |
| 545 | /// ```should_panic |
| 546 | #[doc = concat!("let _ = (" , stringify!($SelfT), "::MAX - 2).strict_add(3);" )] |
| 547 | /// ``` |
| 548 | #[stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 549 | #[rustc_const_stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 550 | #[must_use = "this returns the result of the operation, \ |
| 551 | without modifying the original" ] |
| 552 | #[inline] |
| 553 | #[track_caller] |
| 554 | pub const fn strict_add(self, rhs: Self) -> Self { |
| 555 | let (a, b) = self.overflowing_add(rhs); |
| 556 | if b { overflow_panic::add() } else { a } |
| 557 | } |
| 558 | |
| 559 | /// Unchecked integer addition. Computes `self + rhs`, assuming overflow |
| 560 | /// cannot occur. |
| 561 | /// |
| 562 | /// Calling `x.unchecked_add(y)` is semantically equivalent to calling |
| 563 | /// `x.`[`checked_add`]`(y).`[`unwrap_unchecked`]`()`. |
| 564 | /// |
| 565 | /// If you're just trying to avoid the panic in debug mode, then **do not** |
| 566 | /// use this. Instead, you're looking for [`wrapping_add`]. |
| 567 | /// |
| 568 | /// # Safety |
| 569 | /// |
| 570 | /// This results in undefined behavior when |
| 571 | #[doc = concat!("`self + rhs > " , stringify!($SelfT), "::MAX` or `self + rhs < " , stringify!($SelfT), "::MIN`," )] |
| 572 | /// i.e. when [`checked_add`] would return `None`. |
| 573 | /// |
| 574 | /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked |
| 575 | #[doc = concat!("[`checked_add`]: " , stringify!($SelfT), "::checked_add" )] |
| 576 | #[doc = concat!("[`wrapping_add`]: " , stringify!($SelfT), "::wrapping_add" )] |
| 577 | #[stable(feature = "unchecked_math" , since = "1.79.0" )] |
| 578 | #[rustc_const_stable(feature = "unchecked_math" , since = "1.79.0" )] |
| 579 | #[must_use = "this returns the result of the operation, \ |
| 580 | without modifying the original" ] |
| 581 | #[inline(always)] |
| 582 | #[track_caller] |
| 583 | pub const unsafe fn unchecked_add(self, rhs: Self) -> Self { |
| 584 | assert_unsafe_precondition!( |
| 585 | check_language_ub, |
| 586 | concat!(stringify!($SelfT), "::unchecked_add cannot overflow" ), |
| 587 | ( |
| 588 | lhs: $SelfT = self, |
| 589 | rhs: $SelfT = rhs, |
| 590 | ) => !lhs.overflowing_add(rhs).1, |
| 591 | ); |
| 592 | |
| 593 | // SAFETY: this is guaranteed to be safe by the caller. |
| 594 | unsafe { |
| 595 | intrinsics::unchecked_add(self, rhs) |
| 596 | } |
| 597 | } |
| 598 | |
| 599 | /// Checked addition with an unsigned integer. Computes `self + rhs`, |
| 600 | /// returning `None` if overflow occurred. |
| 601 | /// |
| 602 | /// # Examples |
| 603 | /// |
| 604 | /// ``` |
| 605 | #[doc = concat!("assert_eq!(1" , stringify!($SelfT), ".checked_add_unsigned(2), Some(3));" )] |
| 606 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MAX - 2).checked_add_unsigned(3), None);" )] |
| 607 | /// ``` |
| 608 | #[stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 609 | #[rustc_const_stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 610 | #[must_use = "this returns the result of the operation, \ |
| 611 | without modifying the original" ] |
| 612 | #[inline] |
| 613 | pub const fn checked_add_unsigned(self, rhs: $UnsignedT) -> Option<Self> { |
| 614 | let (a, b) = self.overflowing_add_unsigned(rhs); |
| 615 | if intrinsics::unlikely(b) { None } else { Some(a) } |
| 616 | } |
| 617 | |
| 618 | /// Strict addition with an unsigned integer. Computes `self + rhs`, |
| 619 | /// panicking if overflow occurred. |
| 620 | /// |
| 621 | /// # Panics |
| 622 | /// |
| 623 | /// ## Overflow behavior |
| 624 | /// |
| 625 | /// This function will always panic on overflow, regardless of whether overflow checks are enabled. |
| 626 | /// |
| 627 | /// # Examples |
| 628 | /// |
| 629 | /// ``` |
| 630 | #[doc = concat!("assert_eq!(1" , stringify!($SelfT), ".strict_add_unsigned(2), 3);" )] |
| 631 | /// ``` |
| 632 | /// |
| 633 | /// The following panics because of overflow: |
| 634 | /// |
| 635 | /// ```should_panic |
| 636 | #[doc = concat!("let _ = (" , stringify!($SelfT), "::MAX - 2).strict_add_unsigned(3);" )] |
| 637 | /// ``` |
| 638 | #[stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 639 | #[rustc_const_stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 640 | #[must_use = "this returns the result of the operation, \ |
| 641 | without modifying the original" ] |
| 642 | #[inline] |
| 643 | #[track_caller] |
| 644 | pub const fn strict_add_unsigned(self, rhs: $UnsignedT) -> Self { |
| 645 | let (a, b) = self.overflowing_add_unsigned(rhs); |
| 646 | if b { overflow_panic::add() } else { a } |
| 647 | } |
| 648 | |
| 649 | /// Checked integer subtraction. Computes `self - rhs`, returning `None` if |
| 650 | /// overflow occurred. |
| 651 | /// |
| 652 | /// # Examples |
| 653 | /// |
| 654 | /// ``` |
| 655 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MIN + 2).checked_sub(1), Some(" , stringify!($SelfT), "::MIN + 1));" )] |
| 656 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MIN + 2).checked_sub(3), None);" )] |
| 657 | /// ``` |
| 658 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 659 | #[rustc_const_stable(feature = "const_checked_int_methods" , since = "1.47.0" )] |
| 660 | #[must_use = "this returns the result of the operation, \ |
| 661 | without modifying the original" ] |
| 662 | #[inline] |
| 663 | pub const fn checked_sub(self, rhs: Self) -> Option<Self> { |
| 664 | let (a, b) = self.overflowing_sub(rhs); |
| 665 | if intrinsics::unlikely(b) { None } else { Some(a) } |
| 666 | } |
| 667 | |
| 668 | /// Strict integer subtraction. Computes `self - rhs`, panicking if |
| 669 | /// overflow occurred. |
| 670 | /// |
| 671 | /// # Panics |
| 672 | /// |
| 673 | /// ## Overflow behavior |
| 674 | /// |
| 675 | /// This function will always panic on overflow, regardless of whether overflow checks are enabled. |
| 676 | /// |
| 677 | /// # Examples |
| 678 | /// |
| 679 | /// ``` |
| 680 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MIN + 2).strict_sub(1), " , stringify!($SelfT), "::MIN + 1);" )] |
| 681 | /// ``` |
| 682 | /// |
| 683 | /// The following panics because of overflow: |
| 684 | /// |
| 685 | /// ```should_panic |
| 686 | #[doc = concat!("let _ = (" , stringify!($SelfT), "::MIN + 2).strict_sub(3);" )] |
| 687 | /// ``` |
| 688 | #[stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 689 | #[rustc_const_stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 690 | #[must_use = "this returns the result of the operation, \ |
| 691 | without modifying the original" ] |
| 692 | #[inline] |
| 693 | #[track_caller] |
| 694 | pub const fn strict_sub(self, rhs: Self) -> Self { |
| 695 | let (a, b) = self.overflowing_sub(rhs); |
| 696 | if b { overflow_panic::sub() } else { a } |
| 697 | } |
| 698 | |
| 699 | /// Unchecked integer subtraction. Computes `self - rhs`, assuming overflow |
| 700 | /// cannot occur. |
| 701 | /// |
| 702 | /// Calling `x.unchecked_sub(y)` is semantically equivalent to calling |
| 703 | /// `x.`[`checked_sub`]`(y).`[`unwrap_unchecked`]`()`. |
| 704 | /// |
| 705 | /// If you're just trying to avoid the panic in debug mode, then **do not** |
| 706 | /// use this. Instead, you're looking for [`wrapping_sub`]. |
| 707 | /// |
| 708 | /// # Safety |
| 709 | /// |
| 710 | /// This results in undefined behavior when |
| 711 | #[doc = concat!("`self - rhs > " , stringify!($SelfT), "::MAX` or `self - rhs < " , stringify!($SelfT), "::MIN`," )] |
| 712 | /// i.e. when [`checked_sub`] would return `None`. |
| 713 | /// |
| 714 | /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked |
| 715 | #[doc = concat!("[`checked_sub`]: " , stringify!($SelfT), "::checked_sub" )] |
| 716 | #[doc = concat!("[`wrapping_sub`]: " , stringify!($SelfT), "::wrapping_sub" )] |
| 717 | #[stable(feature = "unchecked_math" , since = "1.79.0" )] |
| 718 | #[rustc_const_stable(feature = "unchecked_math" , since = "1.79.0" )] |
| 719 | #[must_use = "this returns the result of the operation, \ |
| 720 | without modifying the original" ] |
| 721 | #[inline(always)] |
| 722 | #[track_caller] |
| 723 | pub const unsafe fn unchecked_sub(self, rhs: Self) -> Self { |
| 724 | assert_unsafe_precondition!( |
| 725 | check_language_ub, |
| 726 | concat!(stringify!($SelfT), "::unchecked_sub cannot overflow" ), |
| 727 | ( |
| 728 | lhs: $SelfT = self, |
| 729 | rhs: $SelfT = rhs, |
| 730 | ) => !lhs.overflowing_sub(rhs).1, |
| 731 | ); |
| 732 | |
| 733 | // SAFETY: this is guaranteed to be safe by the caller. |
| 734 | unsafe { |
| 735 | intrinsics::unchecked_sub(self, rhs) |
| 736 | } |
| 737 | } |
| 738 | |
| 739 | /// Checked subtraction with an unsigned integer. Computes `self - rhs`, |
| 740 | /// returning `None` if overflow occurred. |
| 741 | /// |
| 742 | /// # Examples |
| 743 | /// |
| 744 | /// ``` |
| 745 | #[doc = concat!("assert_eq!(1" , stringify!($SelfT), ".checked_sub_unsigned(2), Some(-1));" )] |
| 746 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MIN + 2).checked_sub_unsigned(3), None);" )] |
| 747 | /// ``` |
| 748 | #[stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 749 | #[rustc_const_stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 750 | #[must_use = "this returns the result of the operation, \ |
| 751 | without modifying the original" ] |
| 752 | #[inline] |
| 753 | pub const fn checked_sub_unsigned(self, rhs: $UnsignedT) -> Option<Self> { |
| 754 | let (a, b) = self.overflowing_sub_unsigned(rhs); |
| 755 | if intrinsics::unlikely(b) { None } else { Some(a) } |
| 756 | } |
| 757 | |
| 758 | /// Strict subtraction with an unsigned integer. Computes `self - rhs`, |
| 759 | /// panicking if overflow occurred. |
| 760 | /// |
| 761 | /// # Panics |
| 762 | /// |
| 763 | /// ## Overflow behavior |
| 764 | /// |
| 765 | /// This function will always panic on overflow, regardless of whether overflow checks are enabled. |
| 766 | /// |
| 767 | /// # Examples |
| 768 | /// |
| 769 | /// ``` |
| 770 | #[doc = concat!("assert_eq!(1" , stringify!($SelfT), ".strict_sub_unsigned(2), -1);" )] |
| 771 | /// ``` |
| 772 | /// |
| 773 | /// The following panics because of overflow: |
| 774 | /// |
| 775 | /// ```should_panic |
| 776 | #[doc = concat!("let _ = (" , stringify!($SelfT), "::MIN + 2).strict_sub_unsigned(3);" )] |
| 777 | /// ``` |
| 778 | #[stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 779 | #[rustc_const_stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 780 | #[must_use = "this returns the result of the operation, \ |
| 781 | without modifying the original" ] |
| 782 | #[inline] |
| 783 | #[track_caller] |
| 784 | pub const fn strict_sub_unsigned(self, rhs: $UnsignedT) -> Self { |
| 785 | let (a, b) = self.overflowing_sub_unsigned(rhs); |
| 786 | if b { overflow_panic::sub() } else { a } |
| 787 | } |
| 788 | |
| 789 | /// Checked integer multiplication. Computes `self * rhs`, returning `None` if |
| 790 | /// overflow occurred. |
| 791 | /// |
| 792 | /// # Examples |
| 793 | /// |
| 794 | /// ``` |
| 795 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX.checked_mul(1), Some(" , stringify!($SelfT), "::MAX));" )] |
| 796 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX.checked_mul(2), None);" )] |
| 797 | /// ``` |
| 798 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 799 | #[rustc_const_stable(feature = "const_checked_int_methods" , since = "1.47.0" )] |
| 800 | #[must_use = "this returns the result of the operation, \ |
| 801 | without modifying the original" ] |
| 802 | #[inline] |
| 803 | pub const fn checked_mul(self, rhs: Self) -> Option<Self> { |
| 804 | let (a, b) = self.overflowing_mul(rhs); |
| 805 | if intrinsics::unlikely(b) { None } else { Some(a) } |
| 806 | } |
| 807 | |
| 808 | /// Strict integer multiplication. Computes `self * rhs`, panicking if |
| 809 | /// overflow occurred. |
| 810 | /// |
| 811 | /// # Panics |
| 812 | /// |
| 813 | /// ## Overflow behavior |
| 814 | /// |
| 815 | /// This function will always panic on overflow, regardless of whether overflow checks are enabled. |
| 816 | /// |
| 817 | /// # Examples |
| 818 | /// |
| 819 | /// ``` |
| 820 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX.strict_mul(1), " , stringify!($SelfT), "::MAX);" )] |
| 821 | /// ``` |
| 822 | /// |
| 823 | /// The following panics because of overflow: |
| 824 | /// |
| 825 | /// ``` should_panic |
| 826 | #[doc = concat!("let _ = " , stringify!($SelfT), "::MAX.strict_mul(2);" )] |
| 827 | /// ``` |
| 828 | #[stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 829 | #[rustc_const_stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 830 | #[must_use = "this returns the result of the operation, \ |
| 831 | without modifying the original" ] |
| 832 | #[inline] |
| 833 | #[track_caller] |
| 834 | pub const fn strict_mul(self, rhs: Self) -> Self { |
| 835 | let (a, b) = self.overflowing_mul(rhs); |
| 836 | if b { overflow_panic::mul() } else { a } |
| 837 | } |
| 838 | |
| 839 | /// Unchecked integer multiplication. Computes `self * rhs`, assuming overflow |
| 840 | /// cannot occur. |
| 841 | /// |
| 842 | /// Calling `x.unchecked_mul(y)` is semantically equivalent to calling |
| 843 | /// `x.`[`checked_mul`]`(y).`[`unwrap_unchecked`]`()`. |
| 844 | /// |
| 845 | /// If you're just trying to avoid the panic in debug mode, then **do not** |
| 846 | /// use this. Instead, you're looking for [`wrapping_mul`]. |
| 847 | /// |
| 848 | /// # Safety |
| 849 | /// |
| 850 | /// This results in undefined behavior when |
| 851 | #[doc = concat!("`self * rhs > " , stringify!($SelfT), "::MAX` or `self * rhs < " , stringify!($SelfT), "::MIN`," )] |
| 852 | /// i.e. when [`checked_mul`] would return `None`. |
| 853 | /// |
| 854 | /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked |
| 855 | #[doc = concat!("[`checked_mul`]: " , stringify!($SelfT), "::checked_mul" )] |
| 856 | #[doc = concat!("[`wrapping_mul`]: " , stringify!($SelfT), "::wrapping_mul" )] |
| 857 | #[stable(feature = "unchecked_math" , since = "1.79.0" )] |
| 858 | #[rustc_const_stable(feature = "unchecked_math" , since = "1.79.0" )] |
| 859 | #[must_use = "this returns the result of the operation, \ |
| 860 | without modifying the original" ] |
| 861 | #[inline(always)] |
| 862 | #[track_caller] |
| 863 | pub const unsafe fn unchecked_mul(self, rhs: Self) -> Self { |
| 864 | assert_unsafe_precondition!( |
| 865 | check_language_ub, |
| 866 | concat!(stringify!($SelfT), "::unchecked_mul cannot overflow" ), |
| 867 | ( |
| 868 | lhs: $SelfT = self, |
| 869 | rhs: $SelfT = rhs, |
| 870 | ) => !lhs.overflowing_mul(rhs).1, |
| 871 | ); |
| 872 | |
| 873 | // SAFETY: this is guaranteed to be safe by the caller. |
| 874 | unsafe { |
| 875 | intrinsics::unchecked_mul(self, rhs) |
| 876 | } |
| 877 | } |
| 878 | |
| 879 | /// Checked integer division. Computes `self / rhs`, returning `None` if `rhs == 0` |
| 880 | /// or the division results in overflow. |
| 881 | /// |
| 882 | /// # Examples |
| 883 | /// |
| 884 | /// ``` |
| 885 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MIN + 1).checked_div(-1), Some(" , stringify!($Max), "));" )] |
| 886 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.checked_div(-1), None);" )] |
| 887 | #[doc = concat!("assert_eq!((1" , stringify!($SelfT), ").checked_div(0), None);" )] |
| 888 | /// ``` |
| 889 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 890 | #[rustc_const_stable(feature = "const_checked_int_div" , since = "1.52.0" )] |
| 891 | #[must_use = "this returns the result of the operation, \ |
| 892 | without modifying the original" ] |
| 893 | #[inline] |
| 894 | pub const fn checked_div(self, rhs: Self) -> Option<Self> { |
| 895 | if intrinsics::unlikely(rhs == 0 || ((self == Self::MIN) && (rhs == -1))) { |
| 896 | None |
| 897 | } else { |
| 898 | // SAFETY: div by zero and by INT_MIN have been checked above |
| 899 | Some(unsafe { intrinsics::unchecked_div(self, rhs) }) |
| 900 | } |
| 901 | } |
| 902 | |
| 903 | /// Strict integer division. Computes `self / rhs`, panicking |
| 904 | /// if overflow occurred. |
| 905 | /// |
| 906 | /// # Panics |
| 907 | /// |
| 908 | /// This function will panic if `rhs` is zero. |
| 909 | /// |
| 910 | /// ## Overflow behavior |
| 911 | /// |
| 912 | /// This function will always panic on overflow, regardless of whether overflow checks are enabled. |
| 913 | /// |
| 914 | /// The only case where such an overflow can occur is when one divides `MIN / -1` on a signed type (where |
| 915 | /// `MIN` is the negative minimal value for the type); this is equivalent to `-MIN`, a positive value |
| 916 | /// that is too large to represent in the type. |
| 917 | /// |
| 918 | /// # Examples |
| 919 | /// |
| 920 | /// ``` |
| 921 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MIN + 1).strict_div(-1), " , stringify!($Max), ");" )] |
| 922 | /// ``` |
| 923 | /// |
| 924 | /// The following panics because of overflow: |
| 925 | /// |
| 926 | /// ```should_panic |
| 927 | #[doc = concat!("let _ = " , stringify!($SelfT), "::MIN.strict_div(-1);" )] |
| 928 | /// ``` |
| 929 | /// |
| 930 | /// The following panics because of division by zero: |
| 931 | /// |
| 932 | /// ```should_panic |
| 933 | #[doc = concat!("let _ = (1" , stringify!($SelfT), ").strict_div(0);" )] |
| 934 | /// ``` |
| 935 | #[stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 936 | #[rustc_const_stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 937 | #[must_use = "this returns the result of the operation, \ |
| 938 | without modifying the original" ] |
| 939 | #[inline] |
| 940 | #[track_caller] |
| 941 | pub const fn strict_div(self, rhs: Self) -> Self { |
| 942 | let (a, b) = self.overflowing_div(rhs); |
| 943 | if b { overflow_panic::div() } else { a } |
| 944 | } |
| 945 | |
| 946 | /// Checked Euclidean division. Computes `self.div_euclid(rhs)`, |
| 947 | /// returning `None` if `rhs == 0` or the division results in overflow. |
| 948 | /// |
| 949 | /// # Examples |
| 950 | /// |
| 951 | /// ``` |
| 952 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MIN + 1).checked_div_euclid(-1), Some(" , stringify!($Max), "));" )] |
| 953 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.checked_div_euclid(-1), None);" )] |
| 954 | #[doc = concat!("assert_eq!((1" , stringify!($SelfT), ").checked_div_euclid(0), None);" )] |
| 955 | /// ``` |
| 956 | #[stable(feature = "euclidean_division" , since = "1.38.0" )] |
| 957 | #[rustc_const_stable(feature = "const_euclidean_int_methods" , since = "1.52.0" )] |
| 958 | #[must_use = "this returns the result of the operation, \ |
| 959 | without modifying the original" ] |
| 960 | #[inline] |
| 961 | pub const fn checked_div_euclid(self, rhs: Self) -> Option<Self> { |
| 962 | // Using `&` helps LLVM see that it is the same check made in division. |
| 963 | if intrinsics::unlikely(rhs == 0 || ((self == Self::MIN) & (rhs == -1))) { |
| 964 | None |
| 965 | } else { |
| 966 | Some(self.div_euclid(rhs)) |
| 967 | } |
| 968 | } |
| 969 | |
| 970 | /// Strict Euclidean division. Computes `self.div_euclid(rhs)`, panicking |
| 971 | /// if overflow occurred. |
| 972 | /// |
| 973 | /// # Panics |
| 974 | /// |
| 975 | /// This function will panic if `rhs` is zero. |
| 976 | /// |
| 977 | /// ## Overflow behavior |
| 978 | /// |
| 979 | /// This function will always panic on overflow, regardless of whether overflow checks are enabled. |
| 980 | /// |
| 981 | /// The only case where such an overflow can occur is when one divides `MIN / -1` on a signed type (where |
| 982 | /// `MIN` is the negative minimal value for the type); this is equivalent to `-MIN`, a positive value |
| 983 | /// that is too large to represent in the type. |
| 984 | /// |
| 985 | /// # Examples |
| 986 | /// |
| 987 | /// ``` |
| 988 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MIN + 1).strict_div_euclid(-1), " , stringify!($Max), ");" )] |
| 989 | /// ``` |
| 990 | /// |
| 991 | /// The following panics because of overflow: |
| 992 | /// |
| 993 | /// ```should_panic |
| 994 | #[doc = concat!("let _ = " , stringify!($SelfT), "::MIN.strict_div_euclid(-1);" )] |
| 995 | /// ``` |
| 996 | /// |
| 997 | /// The following panics because of division by zero: |
| 998 | /// |
| 999 | /// ```should_panic |
| 1000 | #[doc = concat!("let _ = (1" , stringify!($SelfT), ").strict_div_euclid(0);" )] |
| 1001 | /// ``` |
| 1002 | #[stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1003 | #[rustc_const_stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1004 | #[must_use = "this returns the result of the operation, \ |
| 1005 | without modifying the original" ] |
| 1006 | #[inline] |
| 1007 | #[track_caller] |
| 1008 | pub const fn strict_div_euclid(self, rhs: Self) -> Self { |
| 1009 | let (a, b) = self.overflowing_div_euclid(rhs); |
| 1010 | if b { overflow_panic::div() } else { a } |
| 1011 | } |
| 1012 | |
| 1013 | /// Checked integer division without remainder. Computes `self / rhs`, |
| 1014 | /// returning `None` if `rhs == 0`, the division results in overflow, |
| 1015 | /// or `self % rhs != 0`. |
| 1016 | /// |
| 1017 | /// # Examples |
| 1018 | /// |
| 1019 | /// ``` |
| 1020 | /// #![feature(exact_div)] |
| 1021 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MIN + 1).checked_div_exact(-1), Some(" , stringify!($Max), "));" )] |
| 1022 | #[doc = concat!("assert_eq!((-5" , stringify!($SelfT), ").checked_div_exact(2), None);" )] |
| 1023 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.checked_div_exact(-1), None);" )] |
| 1024 | #[doc = concat!("assert_eq!((1" , stringify!($SelfT), ").checked_div_exact(0), None);" )] |
| 1025 | /// ``` |
| 1026 | #[unstable( |
| 1027 | feature = "exact_div" , |
| 1028 | issue = "139911" , |
| 1029 | )] |
| 1030 | #[must_use = "this returns the result of the operation, \ |
| 1031 | without modifying the original" ] |
| 1032 | #[inline] |
| 1033 | pub const fn checked_div_exact(self, rhs: Self) -> Option<Self> { |
| 1034 | if intrinsics::unlikely(rhs == 0 || ((self == Self::MIN) && (rhs == -1))) { |
| 1035 | None |
| 1036 | } else { |
| 1037 | // SAFETY: division by zero and overflow are checked above |
| 1038 | unsafe { |
| 1039 | if intrinsics::unlikely(intrinsics::unchecked_rem(self, rhs) != 0) { |
| 1040 | None |
| 1041 | } else { |
| 1042 | Some(intrinsics::exact_div(self, rhs)) |
| 1043 | } |
| 1044 | } |
| 1045 | } |
| 1046 | } |
| 1047 | |
| 1048 | /// Integer division without remainder. Computes `self / rhs`, returning `None` if `self % rhs != 0`. |
| 1049 | /// |
| 1050 | /// # Panics |
| 1051 | /// |
| 1052 | /// This function will panic if `rhs == 0`. |
| 1053 | /// |
| 1054 | /// ## Overflow behavior |
| 1055 | /// |
| 1056 | /// On overflow, this function will panic if overflow checks are enabled (default in debug |
| 1057 | /// mode) and wrap if overflow checks are disabled (default in release mode). |
| 1058 | /// |
| 1059 | /// # Examples |
| 1060 | /// |
| 1061 | /// ``` |
| 1062 | /// #![feature(exact_div)] |
| 1063 | #[doc = concat!("assert_eq!(64" , stringify!($SelfT), ".div_exact(2), Some(32));" )] |
| 1064 | #[doc = concat!("assert_eq!(64" , stringify!($SelfT), ".div_exact(32), Some(2));" )] |
| 1065 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MIN + 1).div_exact(-1), Some(" , stringify!($Max), "));" )] |
| 1066 | #[doc = concat!("assert_eq!(65" , stringify!($SelfT), ".div_exact(2), None);" )] |
| 1067 | /// ``` |
| 1068 | /// ```should_panic |
| 1069 | /// #![feature(exact_div)] |
| 1070 | #[doc = concat!("let _ = 64" , stringify!($SelfT),".div_exact(0);" )] |
| 1071 | /// ``` |
| 1072 | /// ```should_panic |
| 1073 | /// #![feature(exact_div)] |
| 1074 | #[doc = concat!("let _ = " , stringify!($SelfT), "::MIN.div_exact(-1);" )] |
| 1075 | /// ``` |
| 1076 | #[unstable( |
| 1077 | feature = "exact_div" , |
| 1078 | issue = "139911" , |
| 1079 | )] |
| 1080 | #[must_use = "this returns the result of the operation, \ |
| 1081 | without modifying the original" ] |
| 1082 | #[inline] |
| 1083 | #[rustc_inherit_overflow_checks] |
| 1084 | pub const fn div_exact(self, rhs: Self) -> Option<Self> { |
| 1085 | if self % rhs != 0 { |
| 1086 | None |
| 1087 | } else { |
| 1088 | Some(self / rhs) |
| 1089 | } |
| 1090 | } |
| 1091 | |
| 1092 | /// Unchecked integer division without remainder. Computes `self / rhs`. |
| 1093 | /// |
| 1094 | /// # Safety |
| 1095 | /// |
| 1096 | /// This results in undefined behavior when `rhs == 0`, `self % rhs != 0`, or |
| 1097 | #[doc = concat!("`self == " , stringify!($SelfT), "::MIN && rhs == -1`," )] |
| 1098 | /// i.e. when [`checked_div_exact`](Self::checked_div_exact) would return `None`. |
| 1099 | #[unstable( |
| 1100 | feature = "exact_div" , |
| 1101 | issue = "139911" , |
| 1102 | )] |
| 1103 | #[must_use = "this returns the result of the operation, \ |
| 1104 | without modifying the original" ] |
| 1105 | #[inline] |
| 1106 | pub const unsafe fn unchecked_div_exact(self, rhs: Self) -> Self { |
| 1107 | assert_unsafe_precondition!( |
| 1108 | check_language_ub, |
| 1109 | concat!(stringify!($SelfT), "::unchecked_div_exact cannot overflow, divide by zero, or leave a remainder" ), |
| 1110 | ( |
| 1111 | lhs: $SelfT = self, |
| 1112 | rhs: $SelfT = rhs, |
| 1113 | ) => rhs > 0 && lhs % rhs == 0 && (lhs != <$SelfT>::MIN || rhs != -1), |
| 1114 | ); |
| 1115 | // SAFETY: Same precondition |
| 1116 | unsafe { intrinsics::exact_div(self, rhs) } |
| 1117 | } |
| 1118 | |
| 1119 | /// Checked integer remainder. Computes `self % rhs`, returning `None` if |
| 1120 | /// `rhs == 0` or the division results in overflow. |
| 1121 | /// |
| 1122 | /// # Examples |
| 1123 | /// |
| 1124 | /// ``` |
| 1125 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".checked_rem(2), Some(1));" )] |
| 1126 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".checked_rem(0), None);" )] |
| 1127 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.checked_rem(-1), None);" )] |
| 1128 | /// ``` |
| 1129 | #[stable(feature = "wrapping" , since = "1.7.0" )] |
| 1130 | #[rustc_const_stable(feature = "const_checked_int_div" , since = "1.52.0" )] |
| 1131 | #[must_use = "this returns the result of the operation, \ |
| 1132 | without modifying the original" ] |
| 1133 | #[inline] |
| 1134 | pub const fn checked_rem(self, rhs: Self) -> Option<Self> { |
| 1135 | if intrinsics::unlikely(rhs == 0 || ((self == Self::MIN) && (rhs == -1))) { |
| 1136 | None |
| 1137 | } else { |
| 1138 | // SAFETY: div by zero and by INT_MIN have been checked above |
| 1139 | Some(unsafe { intrinsics::unchecked_rem(self, rhs) }) |
| 1140 | } |
| 1141 | } |
| 1142 | |
| 1143 | /// Strict integer remainder. Computes `self % rhs`, panicking if |
| 1144 | /// the division results in overflow. |
| 1145 | /// |
| 1146 | /// # Panics |
| 1147 | /// |
| 1148 | /// This function will panic if `rhs` is zero. |
| 1149 | /// |
| 1150 | /// ## Overflow behavior |
| 1151 | /// |
| 1152 | /// This function will always panic on overflow, regardless of whether overflow checks are enabled. |
| 1153 | /// |
| 1154 | /// The only case where such an overflow can occur is `x % y` for `MIN / -1` on a |
| 1155 | /// signed type (where `MIN` is the negative minimal value), which is invalid due to implementation artifacts. |
| 1156 | /// |
| 1157 | /// # Examples |
| 1158 | /// |
| 1159 | /// ``` |
| 1160 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".strict_rem(2), 1);" )] |
| 1161 | /// ``` |
| 1162 | /// |
| 1163 | /// The following panics because of division by zero: |
| 1164 | /// |
| 1165 | /// ```should_panic |
| 1166 | #[doc = concat!("let _ = 5" , stringify!($SelfT), ".strict_rem(0);" )] |
| 1167 | /// ``` |
| 1168 | /// |
| 1169 | /// The following panics because of overflow: |
| 1170 | /// |
| 1171 | /// ```should_panic |
| 1172 | #[doc = concat!("let _ = " , stringify!($SelfT), "::MIN.strict_rem(-1);" )] |
| 1173 | /// ``` |
| 1174 | #[stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1175 | #[rustc_const_stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1176 | #[must_use = "this returns the result of the operation, \ |
| 1177 | without modifying the original" ] |
| 1178 | #[inline] |
| 1179 | #[track_caller] |
| 1180 | pub const fn strict_rem(self, rhs: Self) -> Self { |
| 1181 | let (a, b) = self.overflowing_rem(rhs); |
| 1182 | if b { overflow_panic::rem() } else { a } |
| 1183 | } |
| 1184 | |
| 1185 | /// Checked Euclidean remainder. Computes `self.rem_euclid(rhs)`, returning `None` |
| 1186 | /// if `rhs == 0` or the division results in overflow. |
| 1187 | /// |
| 1188 | /// # Examples |
| 1189 | /// |
| 1190 | /// ``` |
| 1191 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".checked_rem_euclid(2), Some(1));" )] |
| 1192 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".checked_rem_euclid(0), None);" )] |
| 1193 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.checked_rem_euclid(-1), None);" )] |
| 1194 | /// ``` |
| 1195 | #[stable(feature = "euclidean_division" , since = "1.38.0" )] |
| 1196 | #[rustc_const_stable(feature = "const_euclidean_int_methods" , since = "1.52.0" )] |
| 1197 | #[must_use = "this returns the result of the operation, \ |
| 1198 | without modifying the original" ] |
| 1199 | #[inline] |
| 1200 | pub const fn checked_rem_euclid(self, rhs: Self) -> Option<Self> { |
| 1201 | // Using `&` helps LLVM see that it is the same check made in division. |
| 1202 | if intrinsics::unlikely(rhs == 0 || ((self == Self::MIN) & (rhs == -1))) { |
| 1203 | None |
| 1204 | } else { |
| 1205 | Some(self.rem_euclid(rhs)) |
| 1206 | } |
| 1207 | } |
| 1208 | |
| 1209 | /// Strict Euclidean remainder. Computes `self.rem_euclid(rhs)`, panicking if |
| 1210 | /// the division results in overflow. |
| 1211 | /// |
| 1212 | /// # Panics |
| 1213 | /// |
| 1214 | /// This function will panic if `rhs` is zero. |
| 1215 | /// |
| 1216 | /// ## Overflow behavior |
| 1217 | /// |
| 1218 | /// This function will always panic on overflow, regardless of whether overflow checks are enabled. |
| 1219 | /// |
| 1220 | /// The only case where such an overflow can occur is `x % y` for `MIN / -1` on a |
| 1221 | /// signed type (where `MIN` is the negative minimal value), which is invalid due to implementation artifacts. |
| 1222 | /// |
| 1223 | /// # Examples |
| 1224 | /// |
| 1225 | /// ``` |
| 1226 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".strict_rem_euclid(2), 1);" )] |
| 1227 | /// ``` |
| 1228 | /// |
| 1229 | /// The following panics because of division by zero: |
| 1230 | /// |
| 1231 | /// ```should_panic |
| 1232 | #[doc = concat!("let _ = 5" , stringify!($SelfT), ".strict_rem_euclid(0);" )] |
| 1233 | /// ``` |
| 1234 | /// |
| 1235 | /// The following panics because of overflow: |
| 1236 | /// |
| 1237 | /// ```should_panic |
| 1238 | #[doc = concat!("let _ = " , stringify!($SelfT), "::MIN.strict_rem_euclid(-1);" )] |
| 1239 | /// ``` |
| 1240 | #[stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1241 | #[rustc_const_stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1242 | #[must_use = "this returns the result of the operation, \ |
| 1243 | without modifying the original" ] |
| 1244 | #[inline] |
| 1245 | #[track_caller] |
| 1246 | pub const fn strict_rem_euclid(self, rhs: Self) -> Self { |
| 1247 | let (a, b) = self.overflowing_rem_euclid(rhs); |
| 1248 | if b { overflow_panic::rem() } else { a } |
| 1249 | } |
| 1250 | |
| 1251 | /// Checked negation. Computes `-self`, returning `None` if `self == MIN`. |
| 1252 | /// |
| 1253 | /// # Examples |
| 1254 | /// |
| 1255 | /// ``` |
| 1256 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".checked_neg(), Some(-5));" )] |
| 1257 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.checked_neg(), None);" )] |
| 1258 | /// ``` |
| 1259 | #[stable(feature = "wrapping" , since = "1.7.0" )] |
| 1260 | #[rustc_const_stable(feature = "const_checked_int_methods" , since = "1.47.0" )] |
| 1261 | #[must_use = "this returns the result of the operation, \ |
| 1262 | without modifying the original" ] |
| 1263 | #[inline] |
| 1264 | pub const fn checked_neg(self) -> Option<Self> { |
| 1265 | let (a, b) = self.overflowing_neg(); |
| 1266 | if intrinsics::unlikely(b) { None } else { Some(a) } |
| 1267 | } |
| 1268 | |
| 1269 | /// Unchecked negation. Computes `-self`, assuming overflow cannot occur. |
| 1270 | /// |
| 1271 | /// # Safety |
| 1272 | /// |
| 1273 | /// This results in undefined behavior when |
| 1274 | #[doc = concat!("`self == " , stringify!($SelfT), "::MIN`," )] |
| 1275 | /// i.e. when [`checked_neg`] would return `None`. |
| 1276 | /// |
| 1277 | #[doc = concat!("[`checked_neg`]: " , stringify!($SelfT), "::checked_neg" )] |
| 1278 | #[stable(feature = "unchecked_neg" , since = "1.93.0" )] |
| 1279 | #[rustc_const_stable(feature = "unchecked_neg" , since = "1.93.0" )] |
| 1280 | #[must_use = "this returns the result of the operation, \ |
| 1281 | without modifying the original" ] |
| 1282 | #[inline(always)] |
| 1283 | #[track_caller] |
| 1284 | pub const unsafe fn unchecked_neg(self) -> Self { |
| 1285 | assert_unsafe_precondition!( |
| 1286 | check_language_ub, |
| 1287 | concat!(stringify!($SelfT), "::unchecked_neg cannot overflow" ), |
| 1288 | ( |
| 1289 | lhs: $SelfT = self, |
| 1290 | ) => !lhs.overflowing_neg().1, |
| 1291 | ); |
| 1292 | |
| 1293 | // SAFETY: this is guaranteed to be safe by the caller. |
| 1294 | unsafe { |
| 1295 | intrinsics::unchecked_sub(0, self) |
| 1296 | } |
| 1297 | } |
| 1298 | |
| 1299 | /// Strict negation. Computes `-self`, panicking if `self == MIN`. |
| 1300 | /// |
| 1301 | /// # Panics |
| 1302 | /// |
| 1303 | /// ## Overflow behavior |
| 1304 | /// |
| 1305 | /// This function will always panic on overflow, regardless of whether overflow checks are enabled. |
| 1306 | /// |
| 1307 | /// # Examples |
| 1308 | /// |
| 1309 | /// ``` |
| 1310 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".strict_neg(), -5);" )] |
| 1311 | /// ``` |
| 1312 | /// |
| 1313 | /// The following panics because of overflow: |
| 1314 | /// |
| 1315 | /// ```should_panic |
| 1316 | #[doc = concat!("let _ = " , stringify!($SelfT), "::MIN.strict_neg();" )] |
| 1317 | /// ``` |
| 1318 | #[stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1319 | #[rustc_const_stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1320 | #[must_use = "this returns the result of the operation, \ |
| 1321 | without modifying the original" ] |
| 1322 | #[inline] |
| 1323 | #[track_caller] |
| 1324 | pub const fn strict_neg(self) -> Self { |
| 1325 | let (a, b) = self.overflowing_neg(); |
| 1326 | if b { overflow_panic::neg() } else { a } |
| 1327 | } |
| 1328 | |
| 1329 | /// Checked shift left. Computes `self << rhs`, returning `None` if `rhs` is larger |
| 1330 | /// than or equal to the number of bits in `self`. |
| 1331 | /// |
| 1332 | /// # Examples |
| 1333 | /// |
| 1334 | /// ``` |
| 1335 | #[doc = concat!("assert_eq!(0x1" , stringify!($SelfT), ".checked_shl(4), Some(0x10));" )] |
| 1336 | #[doc = concat!("assert_eq!(0x1" , stringify!($SelfT), ".checked_shl(129), None);" )] |
| 1337 | #[doc = concat!("assert_eq!(0x10" , stringify!($SelfT), ".checked_shl(" , stringify!($BITS_MINUS_ONE), "), Some(0));" )] |
| 1338 | /// ``` |
| 1339 | #[stable(feature = "wrapping" , since = "1.7.0" )] |
| 1340 | #[rustc_const_stable(feature = "const_checked_int_methods" , since = "1.47.0" )] |
| 1341 | #[must_use = "this returns the result of the operation, \ |
| 1342 | without modifying the original" ] |
| 1343 | #[inline] |
| 1344 | pub const fn checked_shl(self, rhs: u32) -> Option<Self> { |
| 1345 | // Not using overflowing_shl as that's a wrapping shift |
| 1346 | if rhs < Self::BITS { |
| 1347 | // SAFETY: just checked the RHS is in-range |
| 1348 | Some(unsafe { self.unchecked_shl(rhs) }) |
| 1349 | } else { |
| 1350 | None |
| 1351 | } |
| 1352 | } |
| 1353 | |
| 1354 | /// Strict shift left. Computes `self << rhs`, panicking if `rhs` is larger |
| 1355 | /// than or equal to the number of bits in `self`. |
| 1356 | /// |
| 1357 | /// # Panics |
| 1358 | /// |
| 1359 | /// ## Overflow behavior |
| 1360 | /// |
| 1361 | /// This function will always panic on overflow, regardless of whether overflow checks are enabled. |
| 1362 | /// |
| 1363 | /// # Examples |
| 1364 | /// |
| 1365 | /// ``` |
| 1366 | #[doc = concat!("assert_eq!(0x1" , stringify!($SelfT), ".strict_shl(4), 0x10);" )] |
| 1367 | /// ``` |
| 1368 | /// |
| 1369 | /// The following panics because of overflow: |
| 1370 | /// |
| 1371 | /// ```should_panic |
| 1372 | #[doc = concat!("let _ = 0x1" , stringify!($SelfT), ".strict_shl(129);" )] |
| 1373 | /// ``` |
| 1374 | #[stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1375 | #[rustc_const_stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1376 | #[must_use = "this returns the result of the operation, \ |
| 1377 | without modifying the original" ] |
| 1378 | #[inline] |
| 1379 | #[track_caller] |
| 1380 | pub const fn strict_shl(self, rhs: u32) -> Self { |
| 1381 | let (a, b) = self.overflowing_shl(rhs); |
| 1382 | if b { overflow_panic::shl() } else { a } |
| 1383 | } |
| 1384 | |
| 1385 | /// Unchecked shift left. Computes `self << rhs`, assuming that |
| 1386 | /// `rhs` is less than the number of bits in `self`. |
| 1387 | /// |
| 1388 | /// # Safety |
| 1389 | /// |
| 1390 | /// This results in undefined behavior if `rhs` is larger than |
| 1391 | /// or equal to the number of bits in `self`, |
| 1392 | /// i.e. when [`checked_shl`] would return `None`. |
| 1393 | /// |
| 1394 | #[doc = concat!("[`checked_shl`]: " , stringify!($SelfT), "::checked_shl" )] |
| 1395 | #[stable(feature = "unchecked_shifts" , since = "1.93.0" )] |
| 1396 | #[rustc_const_stable(feature = "unchecked_shifts" , since = "1.93.0" )] |
| 1397 | #[must_use = "this returns the result of the operation, \ |
| 1398 | without modifying the original" ] |
| 1399 | #[inline(always)] |
| 1400 | #[track_caller] |
| 1401 | pub const unsafe fn unchecked_shl(self, rhs: u32) -> Self { |
| 1402 | assert_unsafe_precondition!( |
| 1403 | check_language_ub, |
| 1404 | concat!(stringify!($SelfT), "::unchecked_shl cannot overflow" ), |
| 1405 | ( |
| 1406 | rhs: u32 = rhs, |
| 1407 | ) => rhs < <$ActualT>::BITS, |
| 1408 | ); |
| 1409 | |
| 1410 | // SAFETY: this is guaranteed to be safe by the caller. |
| 1411 | unsafe { |
| 1412 | intrinsics::unchecked_shl(self, rhs) |
| 1413 | } |
| 1414 | } |
| 1415 | |
| 1416 | /// Unbounded shift left. Computes `self << rhs`, without bounding the value of `rhs`. |
| 1417 | /// |
| 1418 | /// If `rhs` is larger or equal to the number of bits in `self`, |
| 1419 | /// the entire value is shifted out, and `0` is returned. |
| 1420 | /// |
| 1421 | /// # Examples |
| 1422 | /// |
| 1423 | /// ``` |
| 1424 | #[doc = concat!("assert_eq!(0x1_" , stringify!($SelfT), ".unbounded_shl(4), 0x10);" )] |
| 1425 | #[doc = concat!("assert_eq!(0x1_" , stringify!($SelfT), ".unbounded_shl(129), 0);" )] |
| 1426 | #[doc = concat!("assert_eq!(0b101_" , stringify!($SelfT), ".unbounded_shl(0), 0b101);" )] |
| 1427 | #[doc = concat!("assert_eq!(0b101_" , stringify!($SelfT), ".unbounded_shl(1), 0b1010);" )] |
| 1428 | #[doc = concat!("assert_eq!(0b101_" , stringify!($SelfT), ".unbounded_shl(2), 0b10100);" )] |
| 1429 | #[doc = concat!("assert_eq!(42_" , stringify!($SelfT), ".unbounded_shl(" , stringify!($BITS), "), 0);" )] |
| 1430 | #[doc = concat!("assert_eq!(42_" , stringify!($SelfT), ".unbounded_shl(1).unbounded_shl(" , stringify!($BITS_MINUS_ONE), "), 0);" )] |
| 1431 | #[doc = concat!("assert_eq!((-13_" , stringify!($SelfT), ").unbounded_shl(" , stringify!($BITS), "), 0);" )] |
| 1432 | #[doc = concat!("assert_eq!((-13_" , stringify!($SelfT), ").unbounded_shl(1).unbounded_shl(" , stringify!($BITS_MINUS_ONE), "), 0);" )] |
| 1433 | /// ``` |
| 1434 | #[stable(feature = "unbounded_shifts" , since = "1.87.0" )] |
| 1435 | #[rustc_const_stable(feature = "unbounded_shifts" , since = "1.87.0" )] |
| 1436 | #[must_use = "this returns the result of the operation, \ |
| 1437 | without modifying the original" ] |
| 1438 | #[inline] |
| 1439 | pub const fn unbounded_shl(self, rhs: u32) -> $SelfT{ |
| 1440 | if rhs < Self::BITS { |
| 1441 | // SAFETY: |
| 1442 | // rhs is just checked to be in-range above |
| 1443 | unsafe { self.unchecked_shl(rhs) } |
| 1444 | } else { |
| 1445 | 0 |
| 1446 | } |
| 1447 | } |
| 1448 | |
| 1449 | /// Exact shift left. Computes `self << rhs` as long as it can be reversed losslessly. |
| 1450 | /// |
| 1451 | /// Returns `None` if any bits that would be shifted out differ from the resulting sign bit |
| 1452 | /// or if `rhs` >= |
| 1453 | #[doc = concat!("`" , stringify!($SelfT), "::BITS`." )] |
| 1454 | /// Otherwise, returns `Some(self << rhs)`. |
| 1455 | /// |
| 1456 | /// # Examples |
| 1457 | /// |
| 1458 | /// ``` |
| 1459 | /// #![feature(exact_bitshifts)] |
| 1460 | /// |
| 1461 | #[doc = concat!("assert_eq!(0x1" , stringify!($SelfT), ".shl_exact(4), Some(0x10));" )] |
| 1462 | #[doc = concat!("assert_eq!(0x1" , stringify!($SelfT), ".shl_exact(" , stringify!($SelfT), "::BITS - 2), Some(1 << " , stringify!($SelfT), "::BITS - 2));" )] |
| 1463 | #[doc = concat!("assert_eq!(0x1" , stringify!($SelfT), ".shl_exact(" , stringify!($SelfT), "::BITS - 1), None);" )] |
| 1464 | #[doc = concat!("assert_eq!((-0x2" , stringify!($SelfT), ").shl_exact(" , stringify!($SelfT), "::BITS - 2), Some(-0x2 << " , stringify!($SelfT), "::BITS - 2));" )] |
| 1465 | #[doc = concat!("assert_eq!((-0x2" , stringify!($SelfT), ").shl_exact(" , stringify!($SelfT), "::BITS - 1), None);" )] |
| 1466 | /// ``` |
| 1467 | #[unstable(feature = "exact_bitshifts" , issue = "144336" )] |
| 1468 | #[must_use = "this returns the result of the operation, \ |
| 1469 | without modifying the original" ] |
| 1470 | #[inline] |
| 1471 | pub const fn shl_exact(self, rhs: u32) -> Option<$SelfT> { |
| 1472 | if rhs < self.leading_zeros() || rhs < self.leading_ones() { |
| 1473 | // SAFETY: rhs is checked above |
| 1474 | Some(unsafe { self.unchecked_shl(rhs) }) |
| 1475 | } else { |
| 1476 | None |
| 1477 | } |
| 1478 | } |
| 1479 | |
| 1480 | /// Unchecked exact shift left. Computes `self << rhs`, assuming the operation can be |
| 1481 | /// losslessly reversed and `rhs` cannot be larger than |
| 1482 | #[doc = concat!("`" , stringify!($SelfT), "::BITS`." )] |
| 1483 | /// |
| 1484 | /// # Safety |
| 1485 | /// |
| 1486 | /// This results in undefined behavior when `rhs >= self.leading_zeros() && rhs >= |
| 1487 | /// self.leading_ones()` i.e. when |
| 1488 | #[doc = concat!("[`" , stringify!($SelfT), "::shl_exact`]" )] |
| 1489 | /// would return `None`. |
| 1490 | #[unstable(feature = "exact_bitshifts" , issue = "144336" )] |
| 1491 | #[must_use = "this returns the result of the operation, \ |
| 1492 | without modifying the original" ] |
| 1493 | #[inline] |
| 1494 | pub const unsafe fn unchecked_shl_exact(self, rhs: u32) -> $SelfT { |
| 1495 | assert_unsafe_precondition!( |
| 1496 | check_library_ub, |
| 1497 | concat!(stringify!($SelfT), "::unchecked_shl_exact cannot shift out bits that would change the value of the first bit" ), |
| 1498 | ( |
| 1499 | zeros: u32 = self.leading_zeros(), |
| 1500 | ones: u32 = self.leading_ones(), |
| 1501 | rhs: u32 = rhs, |
| 1502 | ) => rhs < zeros || rhs < ones, |
| 1503 | ); |
| 1504 | |
| 1505 | // SAFETY: this is guaranteed to be safe by the caller |
| 1506 | unsafe { self.unchecked_shl(rhs) } |
| 1507 | } |
| 1508 | |
| 1509 | /// Checked shift right. Computes `self >> rhs`, returning `None` if `rhs` is |
| 1510 | /// larger than or equal to the number of bits in `self`. |
| 1511 | /// |
| 1512 | /// # Examples |
| 1513 | /// |
| 1514 | /// ``` |
| 1515 | #[doc = concat!("assert_eq!(0x10" , stringify!($SelfT), ".checked_shr(4), Some(0x1));" )] |
| 1516 | #[doc = concat!("assert_eq!(0x10" , stringify!($SelfT), ".checked_shr(128), None);" )] |
| 1517 | /// ``` |
| 1518 | #[stable(feature = "wrapping" , since = "1.7.0" )] |
| 1519 | #[rustc_const_stable(feature = "const_checked_int_methods" , since = "1.47.0" )] |
| 1520 | #[must_use = "this returns the result of the operation, \ |
| 1521 | without modifying the original" ] |
| 1522 | #[inline] |
| 1523 | pub const fn checked_shr(self, rhs: u32) -> Option<Self> { |
| 1524 | // Not using overflowing_shr as that's a wrapping shift |
| 1525 | if rhs < Self::BITS { |
| 1526 | // SAFETY: just checked the RHS is in-range |
| 1527 | Some(unsafe { self.unchecked_shr(rhs) }) |
| 1528 | } else { |
| 1529 | None |
| 1530 | } |
| 1531 | } |
| 1532 | |
| 1533 | /// Strict shift right. Computes `self >> rhs`, panicking if `rhs` is |
| 1534 | /// larger than or equal to the number of bits in `self`. |
| 1535 | /// |
| 1536 | /// # Panics |
| 1537 | /// |
| 1538 | /// ## Overflow behavior |
| 1539 | /// |
| 1540 | /// This function will always panic on overflow, regardless of whether overflow checks are enabled. |
| 1541 | /// |
| 1542 | /// # Examples |
| 1543 | /// |
| 1544 | /// ``` |
| 1545 | #[doc = concat!("assert_eq!(0x10" , stringify!($SelfT), ".strict_shr(4), 0x1);" )] |
| 1546 | /// ``` |
| 1547 | /// |
| 1548 | /// The following panics because of overflow: |
| 1549 | /// |
| 1550 | /// ```should_panic |
| 1551 | #[doc = concat!("let _ = 0x10" , stringify!($SelfT), ".strict_shr(128);" )] |
| 1552 | /// ``` |
| 1553 | #[stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1554 | #[rustc_const_stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1555 | #[must_use = "this returns the result of the operation, \ |
| 1556 | without modifying the original" ] |
| 1557 | #[inline] |
| 1558 | #[track_caller] |
| 1559 | pub const fn strict_shr(self, rhs: u32) -> Self { |
| 1560 | let (a, b) = self.overflowing_shr(rhs); |
| 1561 | if b { overflow_panic::shr() } else { a } |
| 1562 | } |
| 1563 | |
| 1564 | /// Unchecked shift right. Computes `self >> rhs`, assuming that |
| 1565 | /// `rhs` is less than the number of bits in `self`. |
| 1566 | /// |
| 1567 | /// # Safety |
| 1568 | /// |
| 1569 | /// This results in undefined behavior if `rhs` is larger than |
| 1570 | /// or equal to the number of bits in `self`, |
| 1571 | /// i.e. when [`checked_shr`] would return `None`. |
| 1572 | /// |
| 1573 | #[doc = concat!("[`checked_shr`]: " , stringify!($SelfT), "::checked_shr" )] |
| 1574 | #[stable(feature = "unchecked_shifts" , since = "1.93.0" )] |
| 1575 | #[rustc_const_stable(feature = "unchecked_shifts" , since = "1.93.0" )] |
| 1576 | #[must_use = "this returns the result of the operation, \ |
| 1577 | without modifying the original" ] |
| 1578 | #[inline(always)] |
| 1579 | #[track_caller] |
| 1580 | pub const unsafe fn unchecked_shr(self, rhs: u32) -> Self { |
| 1581 | assert_unsafe_precondition!( |
| 1582 | check_language_ub, |
| 1583 | concat!(stringify!($SelfT), "::unchecked_shr cannot overflow" ), |
| 1584 | ( |
| 1585 | rhs: u32 = rhs, |
| 1586 | ) => rhs < <$ActualT>::BITS, |
| 1587 | ); |
| 1588 | |
| 1589 | // SAFETY: this is guaranteed to be safe by the caller. |
| 1590 | unsafe { |
| 1591 | intrinsics::unchecked_shr(self, rhs) |
| 1592 | } |
| 1593 | } |
| 1594 | |
| 1595 | /// Unbounded shift right. Computes `self >> rhs`, without bounding the value of `rhs`. |
| 1596 | /// |
| 1597 | /// If `rhs` is larger or equal to the number of bits in `self`, |
| 1598 | /// the entire value is shifted out, which yields `0` for a positive number, |
| 1599 | /// and `-1` for a negative number. |
| 1600 | /// |
| 1601 | /// # Examples |
| 1602 | /// |
| 1603 | /// ``` |
| 1604 | #[doc = concat!("assert_eq!(0x10_" , stringify!($SelfT), ".unbounded_shr(4), 0x1);" )] |
| 1605 | #[doc = concat!("assert_eq!(0x10_" , stringify!($SelfT), ".unbounded_shr(129), 0);" )] |
| 1606 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.unbounded_shr(129), -1);" )] |
| 1607 | #[doc = concat!("assert_eq!(0b1010_" , stringify!($SelfT), ".unbounded_shr(0), 0b1010);" )] |
| 1608 | #[doc = concat!("assert_eq!(0b1010_" , stringify!($SelfT), ".unbounded_shr(1), 0b101);" )] |
| 1609 | #[doc = concat!("assert_eq!(0b1010_" , stringify!($SelfT), ".unbounded_shr(2), 0b10);" )] |
| 1610 | #[doc = concat!("assert_eq!(42_" , stringify!($SelfT), ".unbounded_shr(" , stringify!($BITS), "), 0);" )] |
| 1611 | #[doc = concat!("assert_eq!(42_" , stringify!($SelfT), ".unbounded_shr(1).unbounded_shr(" , stringify!($BITS_MINUS_ONE), "), 0);" )] |
| 1612 | #[doc = concat!("assert_eq!((-13_" , stringify!($SelfT), ").unbounded_shr(" , stringify!($BITS), "), -1);" )] |
| 1613 | #[doc = concat!("assert_eq!((-13_" , stringify!($SelfT), ").unbounded_shr(1).unbounded_shr(" , stringify!($BITS_MINUS_ONE), "), -1);" )] |
| 1614 | /// ``` |
| 1615 | #[stable(feature = "unbounded_shifts" , since = "1.87.0" )] |
| 1616 | #[rustc_const_stable(feature = "unbounded_shifts" , since = "1.87.0" )] |
| 1617 | #[must_use = "this returns the result of the operation, \ |
| 1618 | without modifying the original" ] |
| 1619 | #[inline] |
| 1620 | pub const fn unbounded_shr(self, rhs: u32) -> $SelfT{ |
| 1621 | if rhs < Self::BITS { |
| 1622 | // SAFETY: |
| 1623 | // rhs is just checked to be in-range above |
| 1624 | unsafe { self.unchecked_shr(rhs) } |
| 1625 | } else { |
| 1626 | // A shift by `Self::BITS-1` suffices for signed integers, because the sign bit is copied for each of the shifted bits. |
| 1627 | |
| 1628 | // SAFETY: |
| 1629 | // `Self::BITS-1` is guaranteed to be less than `Self::BITS` |
| 1630 | unsafe { self.unchecked_shr(Self::BITS - 1) } |
| 1631 | } |
| 1632 | } |
| 1633 | |
| 1634 | /// Exact shift right. Computes `self >> rhs` as long as it can be reversed losslessly. |
| 1635 | /// |
| 1636 | /// Returns `None` if any non-zero bits would be shifted out or if `rhs` >= |
| 1637 | #[doc = concat!("`" , stringify!($SelfT), "::BITS`." )] |
| 1638 | /// Otherwise, returns `Some(self >> rhs)`. |
| 1639 | /// |
| 1640 | /// # Examples |
| 1641 | /// |
| 1642 | /// ``` |
| 1643 | /// #![feature(exact_bitshifts)] |
| 1644 | /// |
| 1645 | #[doc = concat!("assert_eq!(0x10" , stringify!($SelfT), ".shr_exact(4), Some(0x1));" )] |
| 1646 | #[doc = concat!("assert_eq!(0x10" , stringify!($SelfT), ".shr_exact(5), None);" )] |
| 1647 | /// ``` |
| 1648 | #[unstable(feature = "exact_bitshifts" , issue = "144336" )] |
| 1649 | #[must_use = "this returns the result of the operation, \ |
| 1650 | without modifying the original" ] |
| 1651 | #[inline] |
| 1652 | pub const fn shr_exact(self, rhs: u32) -> Option<$SelfT> { |
| 1653 | if rhs <= self.trailing_zeros() && rhs < <$SelfT>::BITS { |
| 1654 | // SAFETY: rhs is checked above |
| 1655 | Some(unsafe { self.unchecked_shr(rhs) }) |
| 1656 | } else { |
| 1657 | None |
| 1658 | } |
| 1659 | } |
| 1660 | |
| 1661 | /// Unchecked exact shift right. Computes `self >> rhs`, assuming the operation can be |
| 1662 | /// losslessly reversed and `rhs` cannot be larger than |
| 1663 | #[doc = concat!("`" , stringify!($SelfT), "::BITS`." )] |
| 1664 | /// |
| 1665 | /// # Safety |
| 1666 | /// |
| 1667 | /// This results in undefined behavior when `rhs > self.trailing_zeros() || rhs >= |
| 1668 | #[doc = concat!(stringify!($SelfT), "::BITS`" )] |
| 1669 | /// i.e. when |
| 1670 | #[doc = concat!("[`" , stringify!($SelfT), "::shr_exact`]" )] |
| 1671 | /// would return `None`. |
| 1672 | #[unstable(feature = "exact_bitshifts" , issue = "144336" )] |
| 1673 | #[must_use = "this returns the result of the operation, \ |
| 1674 | without modifying the original" ] |
| 1675 | #[inline] |
| 1676 | pub const unsafe fn unchecked_shr_exact(self, rhs: u32) -> $SelfT { |
| 1677 | assert_unsafe_precondition!( |
| 1678 | check_library_ub, |
| 1679 | concat!(stringify!($SelfT), "::unchecked_shr_exact cannot shift out non-zero bits" ), |
| 1680 | ( |
| 1681 | zeros: u32 = self.trailing_zeros(), |
| 1682 | bits: u32 = <$SelfT>::BITS, |
| 1683 | rhs: u32 = rhs, |
| 1684 | ) => rhs <= zeros && rhs < bits, |
| 1685 | ); |
| 1686 | |
| 1687 | // SAFETY: this is guaranteed to be safe by the caller |
| 1688 | unsafe { self.unchecked_shr(rhs) } |
| 1689 | } |
| 1690 | |
| 1691 | /// Checked absolute value. Computes `self.abs()`, returning `None` if |
| 1692 | /// `self == MIN`. |
| 1693 | /// |
| 1694 | /// # Examples |
| 1695 | /// |
| 1696 | /// ``` |
| 1697 | #[doc = concat!("assert_eq!((-5" , stringify!($SelfT), ").checked_abs(), Some(5));" )] |
| 1698 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.checked_abs(), None);" )] |
| 1699 | /// ``` |
| 1700 | #[stable(feature = "no_panic_abs" , since = "1.13.0" )] |
| 1701 | #[rustc_const_stable(feature = "const_checked_int_methods" , since = "1.47.0" )] |
| 1702 | #[must_use = "this returns the result of the operation, \ |
| 1703 | without modifying the original" ] |
| 1704 | #[inline] |
| 1705 | pub const fn checked_abs(self) -> Option<Self> { |
| 1706 | if self.is_negative() { |
| 1707 | self.checked_neg() |
| 1708 | } else { |
| 1709 | Some(self) |
| 1710 | } |
| 1711 | } |
| 1712 | |
| 1713 | /// Strict absolute value. Computes `self.abs()`, panicking if |
| 1714 | /// `self == MIN`. |
| 1715 | /// |
| 1716 | /// # Panics |
| 1717 | /// |
| 1718 | /// ## Overflow behavior |
| 1719 | /// |
| 1720 | /// This function will always panic on overflow, regardless of whether overflow checks are enabled. |
| 1721 | /// |
| 1722 | /// # Examples |
| 1723 | /// |
| 1724 | /// ``` |
| 1725 | #[doc = concat!("assert_eq!((-5" , stringify!($SelfT), ").strict_abs(), 5);" )] |
| 1726 | /// ``` |
| 1727 | /// |
| 1728 | /// The following panics because of overflow: |
| 1729 | /// |
| 1730 | /// ```should_panic |
| 1731 | #[doc = concat!("let _ = " , stringify!($SelfT), "::MIN.strict_abs();" )] |
| 1732 | /// ``` |
| 1733 | #[stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1734 | #[rustc_const_stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1735 | #[must_use = "this returns the result of the operation, \ |
| 1736 | without modifying the original" ] |
| 1737 | #[inline] |
| 1738 | #[track_caller] |
| 1739 | pub const fn strict_abs(self) -> Self { |
| 1740 | if self.is_negative() { |
| 1741 | self.strict_neg() |
| 1742 | } else { |
| 1743 | self |
| 1744 | } |
| 1745 | } |
| 1746 | |
| 1747 | /// Checked exponentiation. Computes `self.pow(exp)`, returning `None` if |
| 1748 | /// overflow occurred. |
| 1749 | /// |
| 1750 | /// # Examples |
| 1751 | /// |
| 1752 | /// ``` |
| 1753 | #[doc = concat!("assert_eq!(8" , stringify!($SelfT), ".checked_pow(2), Some(64));" )] |
| 1754 | #[doc = concat!("assert_eq!(0_" , stringify!($SelfT), ".checked_pow(0), Some(1));" )] |
| 1755 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX.checked_pow(2), None);" )] |
| 1756 | /// ``` |
| 1757 | |
| 1758 | #[stable(feature = "no_panic_pow" , since = "1.34.0" )] |
| 1759 | #[rustc_const_stable(feature = "const_int_pow" , since = "1.50.0" )] |
| 1760 | #[must_use = "this returns the result of the operation, \ |
| 1761 | without modifying the original" ] |
| 1762 | #[inline] |
| 1763 | pub const fn checked_pow(self, mut exp: u32) -> Option<Self> { |
| 1764 | if exp == 0 { |
| 1765 | return Some(1); |
| 1766 | } |
| 1767 | let mut base = self; |
| 1768 | let mut acc: Self = 1; |
| 1769 | |
| 1770 | loop { |
| 1771 | if (exp & 1) == 1 { |
| 1772 | acc = try_opt!(acc.checked_mul(base)); |
| 1773 | // since exp!=0, finally the exp must be 1. |
| 1774 | if exp == 1 { |
| 1775 | return Some(acc); |
| 1776 | } |
| 1777 | } |
| 1778 | exp /= 2; |
| 1779 | base = try_opt!(base.checked_mul(base)); |
| 1780 | } |
| 1781 | } |
| 1782 | |
| 1783 | /// Strict exponentiation. Computes `self.pow(exp)`, panicking if |
| 1784 | /// overflow occurred. |
| 1785 | /// |
| 1786 | /// # Panics |
| 1787 | /// |
| 1788 | /// ## Overflow behavior |
| 1789 | /// |
| 1790 | /// This function will always panic on overflow, regardless of whether overflow checks are enabled. |
| 1791 | /// |
| 1792 | /// # Examples |
| 1793 | /// |
| 1794 | /// ``` |
| 1795 | #[doc = concat!("assert_eq!(8" , stringify!($SelfT), ".strict_pow(2), 64);" )] |
| 1796 | #[doc = concat!("assert_eq!(0_" , stringify!($SelfT), ".strict_pow(0), 1);" )] |
| 1797 | /// ``` |
| 1798 | /// |
| 1799 | /// The following panics because of overflow: |
| 1800 | /// |
| 1801 | /// ```should_panic |
| 1802 | #[doc = concat!("let _ = " , stringify!($SelfT), "::MAX.strict_pow(2);" )] |
| 1803 | /// ``` |
| 1804 | #[stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1805 | #[rustc_const_stable(feature = "strict_overflow_ops" , since = "1.91.0" )] |
| 1806 | #[must_use = "this returns the result of the operation, \ |
| 1807 | without modifying the original" ] |
| 1808 | #[inline] |
| 1809 | #[track_caller] |
| 1810 | pub const fn strict_pow(self, mut exp: u32) -> Self { |
| 1811 | if exp == 0 { |
| 1812 | return 1; |
| 1813 | } |
| 1814 | let mut base = self; |
| 1815 | let mut acc: Self = 1; |
| 1816 | |
| 1817 | loop { |
| 1818 | if (exp & 1) == 1 { |
| 1819 | acc = acc.strict_mul(base); |
| 1820 | // since exp!=0, finally the exp must be 1. |
| 1821 | if exp == 1 { |
| 1822 | return acc; |
| 1823 | } |
| 1824 | } |
| 1825 | exp /= 2; |
| 1826 | base = base.strict_mul(base); |
| 1827 | } |
| 1828 | } |
| 1829 | |
| 1830 | /// Returns the square root of the number, rounded down. |
| 1831 | /// |
| 1832 | /// Returns `None` if `self` is negative. |
| 1833 | /// |
| 1834 | /// # Examples |
| 1835 | /// |
| 1836 | /// ``` |
| 1837 | #[doc = concat!("assert_eq!(10" , stringify!($SelfT), ".checked_isqrt(), Some(3));" )] |
| 1838 | /// ``` |
| 1839 | #[stable(feature = "isqrt" , since = "1.84.0" )] |
| 1840 | #[rustc_const_stable(feature = "isqrt" , since = "1.84.0" )] |
| 1841 | #[must_use = "this returns the result of the operation, \ |
| 1842 | without modifying the original" ] |
| 1843 | #[inline] |
| 1844 | pub const fn checked_isqrt(self) -> Option<Self> { |
| 1845 | if self < 0 { |
| 1846 | None |
| 1847 | } else { |
| 1848 | // SAFETY: Input is nonnegative in this `else` branch. |
| 1849 | let result = unsafe { |
| 1850 | crate::num::int_sqrt::$ActualT(self as $ActualT) as $SelfT |
| 1851 | }; |
| 1852 | |
| 1853 | // Inform the optimizer what the range of outputs is. If |
| 1854 | // testing `core` crashes with no panic message and a |
| 1855 | // `num::int_sqrt::i*` test failed, it's because your edits |
| 1856 | // caused these assertions to become false. |
| 1857 | // |
| 1858 | // SAFETY: Integer square root is a monotonically nondecreasing |
| 1859 | // function, which means that increasing the input will never |
| 1860 | // cause the output to decrease. Thus, since the input for |
| 1861 | // nonnegative signed integers is bounded by |
| 1862 | // `[0, <$ActualT>::MAX]`, sqrt(n) will be bounded by |
| 1863 | // `[sqrt(0), sqrt(<$ActualT>::MAX)]`. |
| 1864 | unsafe { |
| 1865 | // SAFETY: `<$ActualT>::MAX` is nonnegative. |
| 1866 | const MAX_RESULT: $SelfT = unsafe { |
| 1867 | crate::num::int_sqrt::$ActualT(<$ActualT>::MAX) as $SelfT |
| 1868 | }; |
| 1869 | |
| 1870 | crate::hint::assert_unchecked(result >= 0); |
| 1871 | crate::hint::assert_unchecked(result <= MAX_RESULT); |
| 1872 | } |
| 1873 | |
| 1874 | Some(result) |
| 1875 | } |
| 1876 | } |
| 1877 | |
| 1878 | /// Saturating integer addition. Computes `self + rhs`, saturating at the numeric |
| 1879 | /// bounds instead of overflowing. |
| 1880 | /// |
| 1881 | /// # Examples |
| 1882 | /// |
| 1883 | /// ``` |
| 1884 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".saturating_add(1), 101);" )] |
| 1885 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX.saturating_add(100), " , stringify!($SelfT), "::MAX);" )] |
| 1886 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.saturating_add(-1), " , stringify!($SelfT), "::MIN);" )] |
| 1887 | /// ``` |
| 1888 | |
| 1889 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 1890 | #[rustc_const_stable(feature = "const_saturating_int_methods" , since = "1.47.0" )] |
| 1891 | #[must_use = "this returns the result of the operation, \ |
| 1892 | without modifying the original" ] |
| 1893 | #[inline(always)] |
| 1894 | pub const fn saturating_add(self, rhs: Self) -> Self { |
| 1895 | intrinsics::saturating_add(self, rhs) |
| 1896 | } |
| 1897 | |
| 1898 | /// Saturating addition with an unsigned integer. Computes `self + rhs`, |
| 1899 | /// saturating at the numeric bounds instead of overflowing. |
| 1900 | /// |
| 1901 | /// # Examples |
| 1902 | /// |
| 1903 | /// ``` |
| 1904 | #[doc = concat!("assert_eq!(1" , stringify!($SelfT), ".saturating_add_unsigned(2), 3);" )] |
| 1905 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX.saturating_add_unsigned(100), " , stringify!($SelfT), "::MAX);" )] |
| 1906 | /// ``` |
| 1907 | #[stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 1908 | #[rustc_const_stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 1909 | #[must_use = "this returns the result of the operation, \ |
| 1910 | without modifying the original" ] |
| 1911 | #[inline] |
| 1912 | pub const fn saturating_add_unsigned(self, rhs: $UnsignedT) -> Self { |
| 1913 | // Overflow can only happen at the upper bound |
| 1914 | // We cannot use `unwrap_or` here because it is not `const` |
| 1915 | match self.checked_add_unsigned(rhs) { |
| 1916 | Some(x) => x, |
| 1917 | None => Self::MAX, |
| 1918 | } |
| 1919 | } |
| 1920 | |
| 1921 | /// Saturating integer subtraction. Computes `self - rhs`, saturating at the |
| 1922 | /// numeric bounds instead of overflowing. |
| 1923 | /// |
| 1924 | /// # Examples |
| 1925 | /// |
| 1926 | /// ``` |
| 1927 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".saturating_sub(127), -27);" )] |
| 1928 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.saturating_sub(100), " , stringify!($SelfT), "::MIN);" )] |
| 1929 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX.saturating_sub(-1), " , stringify!($SelfT), "::MAX);" )] |
| 1930 | /// ``` |
| 1931 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 1932 | #[rustc_const_stable(feature = "const_saturating_int_methods" , since = "1.47.0" )] |
| 1933 | #[must_use = "this returns the result of the operation, \ |
| 1934 | without modifying the original" ] |
| 1935 | #[inline(always)] |
| 1936 | pub const fn saturating_sub(self, rhs: Self) -> Self { |
| 1937 | intrinsics::saturating_sub(self, rhs) |
| 1938 | } |
| 1939 | |
| 1940 | /// Saturating subtraction with an unsigned integer. Computes `self - rhs`, |
| 1941 | /// saturating at the numeric bounds instead of overflowing. |
| 1942 | /// |
| 1943 | /// # Examples |
| 1944 | /// |
| 1945 | /// ``` |
| 1946 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".saturating_sub_unsigned(127), -27);" )] |
| 1947 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.saturating_sub_unsigned(100), " , stringify!($SelfT), "::MIN);" )] |
| 1948 | /// ``` |
| 1949 | #[stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 1950 | #[rustc_const_stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 1951 | #[must_use = "this returns the result of the operation, \ |
| 1952 | without modifying the original" ] |
| 1953 | #[inline] |
| 1954 | pub const fn saturating_sub_unsigned(self, rhs: $UnsignedT) -> Self { |
| 1955 | // Overflow can only happen at the lower bound |
| 1956 | // We cannot use `unwrap_or` here because it is not `const` |
| 1957 | match self.checked_sub_unsigned(rhs) { |
| 1958 | Some(x) => x, |
| 1959 | None => Self::MIN, |
| 1960 | } |
| 1961 | } |
| 1962 | |
| 1963 | /// Saturating integer negation. Computes `-self`, returning `MAX` if `self == MIN` |
| 1964 | /// instead of overflowing. |
| 1965 | /// |
| 1966 | /// # Examples |
| 1967 | /// |
| 1968 | /// ``` |
| 1969 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".saturating_neg(), -100);" )] |
| 1970 | #[doc = concat!("assert_eq!((-100" , stringify!($SelfT), ").saturating_neg(), 100);" )] |
| 1971 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.saturating_neg(), " , stringify!($SelfT), "::MAX);" )] |
| 1972 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX.saturating_neg(), " , stringify!($SelfT), "::MIN + 1);" )] |
| 1973 | /// ``` |
| 1974 | |
| 1975 | #[stable(feature = "saturating_neg" , since = "1.45.0" )] |
| 1976 | #[rustc_const_stable(feature = "const_saturating_int_methods" , since = "1.47.0" )] |
| 1977 | #[must_use = "this returns the result of the operation, \ |
| 1978 | without modifying the original" ] |
| 1979 | #[inline(always)] |
| 1980 | pub const fn saturating_neg(self) -> Self { |
| 1981 | intrinsics::saturating_sub(0, self) |
| 1982 | } |
| 1983 | |
| 1984 | /// Saturating absolute value. Computes `self.abs()`, returning `MAX` if `self == |
| 1985 | /// MIN` instead of overflowing. |
| 1986 | /// |
| 1987 | /// # Examples |
| 1988 | /// |
| 1989 | /// ``` |
| 1990 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".saturating_abs(), 100);" )] |
| 1991 | #[doc = concat!("assert_eq!((-100" , stringify!($SelfT), ").saturating_abs(), 100);" )] |
| 1992 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.saturating_abs(), " , stringify!($SelfT), "::MAX);" )] |
| 1993 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MIN + 1).saturating_abs(), " , stringify!($SelfT), "::MAX);" )] |
| 1994 | /// ``` |
| 1995 | |
| 1996 | #[stable(feature = "saturating_neg" , since = "1.45.0" )] |
| 1997 | #[rustc_const_stable(feature = "const_saturating_int_methods" , since = "1.47.0" )] |
| 1998 | #[must_use = "this returns the result of the operation, \ |
| 1999 | without modifying the original" ] |
| 2000 | #[inline] |
| 2001 | pub const fn saturating_abs(self) -> Self { |
| 2002 | if self.is_negative() { |
| 2003 | self.saturating_neg() |
| 2004 | } else { |
| 2005 | self |
| 2006 | } |
| 2007 | } |
| 2008 | |
| 2009 | /// Saturating integer multiplication. Computes `self * rhs`, saturating at the |
| 2010 | /// numeric bounds instead of overflowing. |
| 2011 | /// |
| 2012 | /// # Examples |
| 2013 | /// |
| 2014 | /// ``` |
| 2015 | #[doc = concat!("assert_eq!(10" , stringify!($SelfT), ".saturating_mul(12), 120);" )] |
| 2016 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX.saturating_mul(10), " , stringify!($SelfT), "::MAX);" )] |
| 2017 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.saturating_mul(10), " , stringify!($SelfT), "::MIN);" )] |
| 2018 | /// ``` |
| 2019 | #[stable(feature = "wrapping" , since = "1.7.0" )] |
| 2020 | #[rustc_const_stable(feature = "const_saturating_int_methods" , since = "1.47.0" )] |
| 2021 | #[must_use = "this returns the result of the operation, \ |
| 2022 | without modifying the original" ] |
| 2023 | #[inline] |
| 2024 | pub const fn saturating_mul(self, rhs: Self) -> Self { |
| 2025 | match self.checked_mul(rhs) { |
| 2026 | Some(x) => x, |
| 2027 | None => if (self < 0) == (rhs < 0) { |
| 2028 | Self::MAX |
| 2029 | } else { |
| 2030 | Self::MIN |
| 2031 | } |
| 2032 | } |
| 2033 | } |
| 2034 | |
| 2035 | /// Saturating integer division. Computes `self / rhs`, saturating at the |
| 2036 | /// numeric bounds instead of overflowing. |
| 2037 | /// |
| 2038 | /// # Panics |
| 2039 | /// |
| 2040 | /// This function will panic if `rhs` is zero. |
| 2041 | /// |
| 2042 | /// # Examples |
| 2043 | /// |
| 2044 | /// ``` |
| 2045 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".saturating_div(2), 2);" )] |
| 2046 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX.saturating_div(-1), " , stringify!($SelfT), "::MIN + 1);" )] |
| 2047 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.saturating_div(-1), " , stringify!($SelfT), "::MAX);" )] |
| 2048 | /// |
| 2049 | /// ``` |
| 2050 | #[stable(feature = "saturating_div" , since = "1.58.0" )] |
| 2051 | #[rustc_const_stable(feature = "saturating_div" , since = "1.58.0" )] |
| 2052 | #[must_use = "this returns the result of the operation, \ |
| 2053 | without modifying the original" ] |
| 2054 | #[inline] |
| 2055 | pub const fn saturating_div(self, rhs: Self) -> Self { |
| 2056 | match self.overflowing_div(rhs) { |
| 2057 | (result, false) => result, |
| 2058 | (_result, true) => Self::MAX, // MIN / -1 is the only possible saturating overflow |
| 2059 | } |
| 2060 | } |
| 2061 | |
| 2062 | /// Saturating integer exponentiation. Computes `self.pow(exp)`, |
| 2063 | /// saturating at the numeric bounds instead of overflowing. |
| 2064 | /// |
| 2065 | /// # Examples |
| 2066 | /// |
| 2067 | /// ``` |
| 2068 | #[doc = concat!("assert_eq!((-4" , stringify!($SelfT), ").saturating_pow(3), -64);" )] |
| 2069 | #[doc = concat!("assert_eq!(0_" , stringify!($SelfT), ".saturating_pow(0), 1);" )] |
| 2070 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.saturating_pow(2), " , stringify!($SelfT), "::MAX);" )] |
| 2071 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.saturating_pow(3), " , stringify!($SelfT), "::MIN);" )] |
| 2072 | /// ``` |
| 2073 | #[stable(feature = "no_panic_pow" , since = "1.34.0" )] |
| 2074 | #[rustc_const_stable(feature = "const_int_pow" , since = "1.50.0" )] |
| 2075 | #[must_use = "this returns the result of the operation, \ |
| 2076 | without modifying the original" ] |
| 2077 | #[inline] |
| 2078 | pub const fn saturating_pow(self, exp: u32) -> Self { |
| 2079 | match self.checked_pow(exp) { |
| 2080 | Some(x) => x, |
| 2081 | None if self < 0 && exp % 2 == 1 => Self::MIN, |
| 2082 | None => Self::MAX, |
| 2083 | } |
| 2084 | } |
| 2085 | |
| 2086 | /// Wrapping (modular) addition. Computes `self + rhs`, wrapping around at the |
| 2087 | /// boundary of the type. |
| 2088 | /// |
| 2089 | /// # Examples |
| 2090 | /// |
| 2091 | /// ``` |
| 2092 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".wrapping_add(27), 127);" )] |
| 2093 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX.wrapping_add(2), " , stringify!($SelfT), "::MIN + 1);" )] |
| 2094 | /// ``` |
| 2095 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 2096 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 2097 | #[must_use = "this returns the result of the operation, \ |
| 2098 | without modifying the original" ] |
| 2099 | #[inline(always)] |
| 2100 | pub const fn wrapping_add(self, rhs: Self) -> Self { |
| 2101 | intrinsics::wrapping_add(self, rhs) |
| 2102 | } |
| 2103 | |
| 2104 | /// Wrapping (modular) addition with an unsigned integer. Computes |
| 2105 | /// `self + rhs`, wrapping around at the boundary of the type. |
| 2106 | /// |
| 2107 | /// # Examples |
| 2108 | /// |
| 2109 | /// ``` |
| 2110 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".wrapping_add_unsigned(27), 127);" )] |
| 2111 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX.wrapping_add_unsigned(2), " , stringify!($SelfT), "::MIN + 1);" )] |
| 2112 | /// ``` |
| 2113 | #[stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 2114 | #[rustc_const_stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 2115 | #[must_use = "this returns the result of the operation, \ |
| 2116 | without modifying the original" ] |
| 2117 | #[inline(always)] |
| 2118 | pub const fn wrapping_add_unsigned(self, rhs: $UnsignedT) -> Self { |
| 2119 | self.wrapping_add(rhs as Self) |
| 2120 | } |
| 2121 | |
| 2122 | /// Wrapping (modular) subtraction. Computes `self - rhs`, wrapping around at the |
| 2123 | /// boundary of the type. |
| 2124 | /// |
| 2125 | /// # Examples |
| 2126 | /// |
| 2127 | /// ``` |
| 2128 | #[doc = concat!("assert_eq!(0" , stringify!($SelfT), ".wrapping_sub(127), -127);" )] |
| 2129 | #[doc = concat!("assert_eq!((-2" , stringify!($SelfT), ").wrapping_sub(" , stringify!($SelfT), "::MAX), " , stringify!($SelfT), "::MAX);" )] |
| 2130 | /// ``` |
| 2131 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 2132 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 2133 | #[must_use = "this returns the result of the operation, \ |
| 2134 | without modifying the original" ] |
| 2135 | #[inline(always)] |
| 2136 | pub const fn wrapping_sub(self, rhs: Self) -> Self { |
| 2137 | intrinsics::wrapping_sub(self, rhs) |
| 2138 | } |
| 2139 | |
| 2140 | /// Wrapping (modular) subtraction with an unsigned integer. Computes |
| 2141 | /// `self - rhs`, wrapping around at the boundary of the type. |
| 2142 | /// |
| 2143 | /// # Examples |
| 2144 | /// |
| 2145 | /// ``` |
| 2146 | #[doc = concat!("assert_eq!(0" , stringify!($SelfT), ".wrapping_sub_unsigned(127), -127);" )] |
| 2147 | #[doc = concat!("assert_eq!((-2" , stringify!($SelfT), ").wrapping_sub_unsigned(" , stringify!($UnsignedT), "::MAX), -1);" )] |
| 2148 | /// ``` |
| 2149 | #[stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 2150 | #[rustc_const_stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 2151 | #[must_use = "this returns the result of the operation, \ |
| 2152 | without modifying the original" ] |
| 2153 | #[inline(always)] |
| 2154 | pub const fn wrapping_sub_unsigned(self, rhs: $UnsignedT) -> Self { |
| 2155 | self.wrapping_sub(rhs as Self) |
| 2156 | } |
| 2157 | |
| 2158 | /// Wrapping (modular) multiplication. Computes `self * rhs`, wrapping around at |
| 2159 | /// the boundary of the type. |
| 2160 | /// |
| 2161 | /// # Examples |
| 2162 | /// |
| 2163 | /// ``` |
| 2164 | #[doc = concat!("assert_eq!(10" , stringify!($SelfT), ".wrapping_mul(12), 120);" )] |
| 2165 | /// assert_eq!(11i8.wrapping_mul(12), -124); |
| 2166 | /// ``` |
| 2167 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 2168 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 2169 | #[must_use = "this returns the result of the operation, \ |
| 2170 | without modifying the original" ] |
| 2171 | #[inline(always)] |
| 2172 | pub const fn wrapping_mul(self, rhs: Self) -> Self { |
| 2173 | intrinsics::wrapping_mul(self, rhs) |
| 2174 | } |
| 2175 | |
| 2176 | /// Wrapping (modular) division. Computes `self / rhs`, wrapping around at the |
| 2177 | /// boundary of the type. |
| 2178 | /// |
| 2179 | /// The only case where such wrapping can occur is when one divides `MIN / -1` on a signed type (where |
| 2180 | /// `MIN` is the negative minimal value for the type); this is equivalent to `-MIN`, a positive value |
| 2181 | /// that is too large to represent in the type. In such a case, this function returns `MIN` itself. |
| 2182 | /// |
| 2183 | /// # Panics |
| 2184 | /// |
| 2185 | /// This function will panic if `rhs` is zero. |
| 2186 | /// |
| 2187 | /// # Examples |
| 2188 | /// |
| 2189 | /// ``` |
| 2190 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".wrapping_div(10), 10);" )] |
| 2191 | /// assert_eq!((-128i8).wrapping_div(-1), -128); |
| 2192 | /// ``` |
| 2193 | #[stable(feature = "num_wrapping" , since = "1.2.0" )] |
| 2194 | #[rustc_const_stable(feature = "const_wrapping_int_methods" , since = "1.52.0" )] |
| 2195 | #[must_use = "this returns the result of the operation, \ |
| 2196 | without modifying the original" ] |
| 2197 | #[inline] |
| 2198 | pub const fn wrapping_div(self, rhs: Self) -> Self { |
| 2199 | self.overflowing_div(rhs).0 |
| 2200 | } |
| 2201 | |
| 2202 | /// Wrapping Euclidean division. Computes `self.div_euclid(rhs)`, |
| 2203 | /// wrapping around at the boundary of the type. |
| 2204 | /// |
| 2205 | /// Wrapping will only occur in `MIN / -1` on a signed type (where `MIN` is the negative minimal value |
| 2206 | /// for the type). This is equivalent to `-MIN`, a positive value that is too large to represent in the |
| 2207 | /// type. In this case, this method returns `MIN` itself. |
| 2208 | /// |
| 2209 | /// # Panics |
| 2210 | /// |
| 2211 | /// This function will panic if `rhs` is zero. |
| 2212 | /// |
| 2213 | /// # Examples |
| 2214 | /// |
| 2215 | /// ``` |
| 2216 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".wrapping_div_euclid(10), 10);" )] |
| 2217 | /// assert_eq!((-128i8).wrapping_div_euclid(-1), -128); |
| 2218 | /// ``` |
| 2219 | #[stable(feature = "euclidean_division" , since = "1.38.0" )] |
| 2220 | #[rustc_const_stable(feature = "const_euclidean_int_methods" , since = "1.52.0" )] |
| 2221 | #[must_use = "this returns the result of the operation, \ |
| 2222 | without modifying the original" ] |
| 2223 | #[inline] |
| 2224 | pub const fn wrapping_div_euclid(self, rhs: Self) -> Self { |
| 2225 | self.overflowing_div_euclid(rhs).0 |
| 2226 | } |
| 2227 | |
| 2228 | /// Wrapping (modular) remainder. Computes `self % rhs`, wrapping around at the |
| 2229 | /// boundary of the type. |
| 2230 | /// |
| 2231 | /// Such wrap-around never actually occurs mathematically; implementation artifacts make `x % y` |
| 2232 | /// invalid for `MIN / -1` on a signed type (where `MIN` is the negative minimal value). In such a case, |
| 2233 | /// this function returns `0`. |
| 2234 | /// |
| 2235 | /// # Panics |
| 2236 | /// |
| 2237 | /// This function will panic if `rhs` is zero. |
| 2238 | /// |
| 2239 | /// # Examples |
| 2240 | /// |
| 2241 | /// ``` |
| 2242 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".wrapping_rem(10), 0);" )] |
| 2243 | /// assert_eq!((-128i8).wrapping_rem(-1), 0); |
| 2244 | /// ``` |
| 2245 | #[stable(feature = "num_wrapping" , since = "1.2.0" )] |
| 2246 | #[rustc_const_stable(feature = "const_wrapping_int_methods" , since = "1.52.0" )] |
| 2247 | #[must_use = "this returns the result of the operation, \ |
| 2248 | without modifying the original" ] |
| 2249 | #[inline] |
| 2250 | pub const fn wrapping_rem(self, rhs: Self) -> Self { |
| 2251 | self.overflowing_rem(rhs).0 |
| 2252 | } |
| 2253 | |
| 2254 | /// Wrapping Euclidean remainder. Computes `self.rem_euclid(rhs)`, wrapping around |
| 2255 | /// at the boundary of the type. |
| 2256 | /// |
| 2257 | /// Wrapping will only occur in `MIN % -1` on a signed type (where `MIN` is the negative minimal value |
| 2258 | /// for the type). In this case, this method returns 0. |
| 2259 | /// |
| 2260 | /// # Panics |
| 2261 | /// |
| 2262 | /// This function will panic if `rhs` is zero. |
| 2263 | /// |
| 2264 | /// # Examples |
| 2265 | /// |
| 2266 | /// ``` |
| 2267 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".wrapping_rem_euclid(10), 0);" )] |
| 2268 | /// assert_eq!((-128i8).wrapping_rem_euclid(-1), 0); |
| 2269 | /// ``` |
| 2270 | #[stable(feature = "euclidean_division" , since = "1.38.0" )] |
| 2271 | #[rustc_const_stable(feature = "const_euclidean_int_methods" , since = "1.52.0" )] |
| 2272 | #[must_use = "this returns the result of the operation, \ |
| 2273 | without modifying the original" ] |
| 2274 | #[inline] |
| 2275 | pub const fn wrapping_rem_euclid(self, rhs: Self) -> Self { |
| 2276 | self.overflowing_rem_euclid(rhs).0 |
| 2277 | } |
| 2278 | |
| 2279 | /// Wrapping (modular) negation. Computes `-self`, wrapping around at the boundary |
| 2280 | /// of the type. |
| 2281 | /// |
| 2282 | /// The only case where such wrapping can occur is when one negates `MIN` on a signed type (where `MIN` |
| 2283 | /// is the negative minimal value for the type); this is a positive value that is too large to represent |
| 2284 | /// in the type. In such a case, this function returns `MIN` itself. |
| 2285 | /// |
| 2286 | /// # Examples |
| 2287 | /// |
| 2288 | /// ``` |
| 2289 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".wrapping_neg(), -100);" )] |
| 2290 | #[doc = concat!("assert_eq!((-100" , stringify!($SelfT), ").wrapping_neg(), 100);" )] |
| 2291 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.wrapping_neg(), " , stringify!($SelfT), "::MIN);" )] |
| 2292 | /// ``` |
| 2293 | #[stable(feature = "num_wrapping" , since = "1.2.0" )] |
| 2294 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 2295 | #[must_use = "this returns the result of the operation, \ |
| 2296 | without modifying the original" ] |
| 2297 | #[inline(always)] |
| 2298 | pub const fn wrapping_neg(self) -> Self { |
| 2299 | (0 as $SelfT).wrapping_sub(self) |
| 2300 | } |
| 2301 | |
| 2302 | /// Panic-free bitwise shift-left; yields `self << mask(rhs)`, where `mask` removes |
| 2303 | /// any high-order bits of `rhs` that would cause the shift to exceed the bitwidth of the type. |
| 2304 | /// |
| 2305 | /// Beware that, unlike most other `wrapping_*` methods on integers, this |
| 2306 | /// does *not* give the same result as doing the shift in infinite precision |
| 2307 | /// then truncating as needed. The behaviour matches what shift instructions |
| 2308 | /// do on many processors, and is what the `<<` operator does when overflow |
| 2309 | /// checks are disabled, but numerically it's weird. Consider, instead, |
| 2310 | /// using [`Self::unbounded_shl`] which has nicer behaviour. |
| 2311 | /// |
| 2312 | /// Note that this is *not* the same as a rotate-left; the RHS of a wrapping shift-left is restricted to |
| 2313 | /// the range of the type, rather than the bits shifted out of the LHS being returned to the other end. |
| 2314 | /// The primitive integer types all implement a [`rotate_left`](Self::rotate_left) function, |
| 2315 | /// which may be what you want instead. |
| 2316 | /// |
| 2317 | /// # Examples |
| 2318 | /// |
| 2319 | /// ``` |
| 2320 | #[doc = concat!("assert_eq!((-1_" , stringify!($SelfT), ").wrapping_shl(7), -128);" )] |
| 2321 | #[doc = concat!("assert_eq!(42_" , stringify!($SelfT), ".wrapping_shl(" , stringify!($BITS), "), 42);" )] |
| 2322 | #[doc = concat!("assert_eq!(42_" , stringify!($SelfT), ".wrapping_shl(1).wrapping_shl(" , stringify!($BITS_MINUS_ONE), "), 0);" )] |
| 2323 | #[doc = concat!("assert_eq!((-1_" , stringify!($SelfT), ").wrapping_shl(128), -1);" )] |
| 2324 | #[doc = concat!("assert_eq!(5_" , stringify!($SelfT), ".wrapping_shl(1025), 10);" )] |
| 2325 | /// ``` |
| 2326 | #[stable(feature = "num_wrapping" , since = "1.2.0" )] |
| 2327 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 2328 | #[must_use = "this returns the result of the operation, \ |
| 2329 | without modifying the original" ] |
| 2330 | #[inline(always)] |
| 2331 | pub const fn wrapping_shl(self, rhs: u32) -> Self { |
| 2332 | // SAFETY: the masking by the bitsize of the type ensures that we do not shift |
| 2333 | // out of bounds |
| 2334 | unsafe { |
| 2335 | self.unchecked_shl(rhs & (Self::BITS - 1)) |
| 2336 | } |
| 2337 | } |
| 2338 | |
| 2339 | /// Panic-free bitwise shift-right; yields `self >> mask(rhs)`, where `mask` |
| 2340 | /// removes any high-order bits of `rhs` that would cause the shift to exceed the bitwidth of the type. |
| 2341 | /// |
| 2342 | /// Beware that, unlike most other `wrapping_*` methods on integers, this |
| 2343 | /// does *not* give the same result as doing the shift in infinite precision |
| 2344 | /// then truncating as needed. The behaviour matches what shift instructions |
| 2345 | /// do on many processors, and is what the `>>` operator does when overflow |
| 2346 | /// checks are disabled, but numerically it's weird. Consider, instead, |
| 2347 | /// using [`Self::unbounded_shr`] which has nicer behaviour. |
| 2348 | /// |
| 2349 | /// Note that this is *not* the same as a rotate-right; the RHS of a wrapping shift-right is restricted |
| 2350 | /// to the range of the type, rather than the bits shifted out of the LHS being returned to the other |
| 2351 | /// end. The primitive integer types all implement a [`rotate_right`](Self::rotate_right) function, |
| 2352 | /// which may be what you want instead. |
| 2353 | /// |
| 2354 | /// # Examples |
| 2355 | /// |
| 2356 | /// ``` |
| 2357 | #[doc = concat!("assert_eq!((-128_" , stringify!($SelfT), ").wrapping_shr(7), -1);" )] |
| 2358 | #[doc = concat!("assert_eq!(42_" , stringify!($SelfT), ".wrapping_shr(" , stringify!($BITS), "), 42);" )] |
| 2359 | #[doc = concat!("assert_eq!(42_" , stringify!($SelfT), ".wrapping_shr(1).wrapping_shr(" , stringify!($BITS_MINUS_ONE), "), 0);" )] |
| 2360 | /// assert_eq!((-128_i16).wrapping_shr(64), -128); |
| 2361 | #[doc = concat!("assert_eq!(10_" , stringify!($SelfT), ".wrapping_shr(1025), 5);" )] |
| 2362 | /// ``` |
| 2363 | #[stable(feature = "num_wrapping" , since = "1.2.0" )] |
| 2364 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 2365 | #[must_use = "this returns the result of the operation, \ |
| 2366 | without modifying the original" ] |
| 2367 | #[inline(always)] |
| 2368 | pub const fn wrapping_shr(self, rhs: u32) -> Self { |
| 2369 | // SAFETY: the masking by the bitsize of the type ensures that we do not shift |
| 2370 | // out of bounds |
| 2371 | unsafe { |
| 2372 | self.unchecked_shr(rhs & (Self::BITS - 1)) |
| 2373 | } |
| 2374 | } |
| 2375 | |
| 2376 | /// Wrapping (modular) absolute value. Computes `self.abs()`, wrapping around at |
| 2377 | /// the boundary of the type. |
| 2378 | /// |
| 2379 | /// The only case where such wrapping can occur is when one takes the absolute value of the negative |
| 2380 | /// minimal value for the type; this is a positive value that is too large to represent in the type. In |
| 2381 | /// such a case, this function returns `MIN` itself. |
| 2382 | /// |
| 2383 | /// # Examples |
| 2384 | /// |
| 2385 | /// ``` |
| 2386 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".wrapping_abs(), 100);" )] |
| 2387 | #[doc = concat!("assert_eq!((-100" , stringify!($SelfT), ").wrapping_abs(), 100);" )] |
| 2388 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.wrapping_abs(), " , stringify!($SelfT), "::MIN);" )] |
| 2389 | /// assert_eq!((-128i8).wrapping_abs() as u8, 128); |
| 2390 | /// ``` |
| 2391 | #[stable(feature = "no_panic_abs" , since = "1.13.0" )] |
| 2392 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 2393 | #[must_use = "this returns the result of the operation, \ |
| 2394 | without modifying the original" ] |
| 2395 | #[allow(unused_attributes)] |
| 2396 | #[inline] |
| 2397 | pub const fn wrapping_abs(self) -> Self { |
| 2398 | if self.is_negative() { |
| 2399 | self.wrapping_neg() |
| 2400 | } else { |
| 2401 | self |
| 2402 | } |
| 2403 | } |
| 2404 | |
| 2405 | /// Computes the absolute value of `self` without any wrapping |
| 2406 | /// or panicking. |
| 2407 | /// |
| 2408 | /// |
| 2409 | /// # Examples |
| 2410 | /// |
| 2411 | /// ``` |
| 2412 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".unsigned_abs(), 100" , stringify!($UnsignedT), ");" )] |
| 2413 | #[doc = concat!("assert_eq!((-100" , stringify!($SelfT), ").unsigned_abs(), 100" , stringify!($UnsignedT), ");" )] |
| 2414 | /// assert_eq!((-128i8).unsigned_abs(), 128u8); |
| 2415 | /// ``` |
| 2416 | #[stable(feature = "unsigned_abs" , since = "1.51.0" )] |
| 2417 | #[rustc_const_stable(feature = "unsigned_abs" , since = "1.51.0" )] |
| 2418 | #[must_use = "this returns the result of the operation, \ |
| 2419 | without modifying the original" ] |
| 2420 | #[inline] |
| 2421 | pub const fn unsigned_abs(self) -> $UnsignedT { |
| 2422 | self.wrapping_abs() as $UnsignedT |
| 2423 | } |
| 2424 | |
| 2425 | /// Wrapping (modular) exponentiation. Computes `self.pow(exp)`, |
| 2426 | /// wrapping around at the boundary of the type. |
| 2427 | /// |
| 2428 | /// # Examples |
| 2429 | /// |
| 2430 | /// ``` |
| 2431 | #[doc = concat!("assert_eq!(3" , stringify!($SelfT), ".wrapping_pow(4), 81);" )] |
| 2432 | /// assert_eq!(3i8.wrapping_pow(5), -13); |
| 2433 | /// assert_eq!(3i8.wrapping_pow(6), -39); |
| 2434 | #[doc = concat!("assert_eq!(0_" , stringify!($SelfT), ".wrapping_pow(0), 1);" )] |
| 2435 | /// ``` |
| 2436 | #[stable(feature = "no_panic_pow" , since = "1.34.0" )] |
| 2437 | #[rustc_const_stable(feature = "const_int_pow" , since = "1.50.0" )] |
| 2438 | #[must_use = "this returns the result of the operation, \ |
| 2439 | without modifying the original" ] |
| 2440 | #[inline] |
| 2441 | pub const fn wrapping_pow(self, mut exp: u32) -> Self { |
| 2442 | if exp == 0 { |
| 2443 | return 1; |
| 2444 | } |
| 2445 | let mut base = self; |
| 2446 | let mut acc: Self = 1; |
| 2447 | |
| 2448 | if intrinsics::is_val_statically_known(exp) { |
| 2449 | while exp > 1 { |
| 2450 | if (exp & 1) == 1 { |
| 2451 | acc = acc.wrapping_mul(base); |
| 2452 | } |
| 2453 | exp /= 2; |
| 2454 | base = base.wrapping_mul(base); |
| 2455 | } |
| 2456 | |
| 2457 | // since exp!=0, finally the exp must be 1. |
| 2458 | // Deal with the final bit of the exponent separately, since |
| 2459 | // squaring the base afterwards is not necessary. |
| 2460 | acc.wrapping_mul(base) |
| 2461 | } else { |
| 2462 | // This is faster than the above when the exponent is not known |
| 2463 | // at compile time. We can't use the same code for the constant |
| 2464 | // exponent case because LLVM is currently unable to unroll |
| 2465 | // this loop. |
| 2466 | loop { |
| 2467 | if (exp & 1) == 1 { |
| 2468 | acc = acc.wrapping_mul(base); |
| 2469 | // since exp!=0, finally the exp must be 1. |
| 2470 | if exp == 1 { |
| 2471 | return acc; |
| 2472 | } |
| 2473 | } |
| 2474 | exp /= 2; |
| 2475 | base = base.wrapping_mul(base); |
| 2476 | } |
| 2477 | } |
| 2478 | } |
| 2479 | |
| 2480 | /// Calculates `self` + `rhs`. |
| 2481 | /// |
| 2482 | /// Returns a tuple of the addition along with a boolean indicating |
| 2483 | /// whether an arithmetic overflow would occur. If an overflow would have |
| 2484 | /// occurred then the wrapped value is returned. |
| 2485 | /// |
| 2486 | /// # Examples |
| 2487 | /// |
| 2488 | /// ``` |
| 2489 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".overflowing_add(2), (7, false));" )] |
| 2490 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX.overflowing_add(1), (" , stringify!($SelfT), "::MIN, true));" )] |
| 2491 | /// ``` |
| 2492 | #[stable(feature = "wrapping" , since = "1.7.0" )] |
| 2493 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 2494 | #[must_use = "this returns the result of the operation, \ |
| 2495 | without modifying the original" ] |
| 2496 | #[inline(always)] |
| 2497 | pub const fn overflowing_add(self, rhs: Self) -> (Self, bool) { |
| 2498 | let (a, b) = intrinsics::add_with_overflow(self as $ActualT, rhs as $ActualT); |
| 2499 | (a as Self, b) |
| 2500 | } |
| 2501 | |
| 2502 | /// Calculates `self` + `rhs` + `carry` and checks for overflow. |
| 2503 | /// |
| 2504 | /// Performs "ternary addition" of two integer operands and a carry-in |
| 2505 | /// bit, and returns a tuple of the sum along with a boolean indicating |
| 2506 | /// whether an arithmetic overflow would occur. On overflow, the wrapped |
| 2507 | /// value is returned. |
| 2508 | /// |
| 2509 | /// This allows chaining together multiple additions to create a wider |
| 2510 | /// addition, and can be useful for bignum addition. This method should |
| 2511 | /// only be used for the most significant word; for the less significant |
| 2512 | /// words the unsigned method |
| 2513 | #[doc = concat!("[`" , stringify!($UnsignedT), "::carrying_add`]" )] |
| 2514 | /// should be used. |
| 2515 | /// |
| 2516 | /// The output boolean returned by this method is *not* a carry flag, |
| 2517 | /// and should *not* be added to a more significant word. |
| 2518 | /// |
| 2519 | /// If the input carry is false, this method is equivalent to |
| 2520 | /// [`overflowing_add`](Self::overflowing_add). |
| 2521 | /// |
| 2522 | /// # Examples |
| 2523 | /// |
| 2524 | /// ``` |
| 2525 | /// #![feature(signed_bigint_helpers)] |
| 2526 | /// // Only the most significant word is signed. |
| 2527 | /// // |
| 2528 | #[doc = concat!("// 10 MAX (a = 10 × 2^" , stringify!($BITS), " + 2^" , stringify!($BITS), " - 1)" )] |
| 2529 | #[doc = concat!("// + -5 9 (b = -5 × 2^" , stringify!($BITS), " + 9)" )] |
| 2530 | /// // --------- |
| 2531 | #[doc = concat!("// 6 8 (sum = 6 × 2^" , stringify!($BITS), " + 8)" )] |
| 2532 | /// |
| 2533 | #[doc = concat!("let (a1, a0): (" , stringify!($SelfT), ", " , stringify!($UnsignedT), ") = (10, " , stringify!($UnsignedT), "::MAX);" )] |
| 2534 | #[doc = concat!("let (b1, b0): (" , stringify!($SelfT), ", " , stringify!($UnsignedT), ") = (-5, 9);" )] |
| 2535 | /// let carry0 = false; |
| 2536 | /// |
| 2537 | #[doc = concat!("// " , stringify!($UnsignedT), "::carrying_add for the less significant words" )] |
| 2538 | /// let (sum0, carry1) = a0.carrying_add(b0, carry0); |
| 2539 | /// assert_eq!(carry1, true); |
| 2540 | /// |
| 2541 | #[doc = concat!("// " , stringify!($SelfT), "::carrying_add for the most significant word" )] |
| 2542 | /// let (sum1, overflow) = a1.carrying_add(b1, carry1); |
| 2543 | /// assert_eq!(overflow, false); |
| 2544 | /// |
| 2545 | /// assert_eq!((sum1, sum0), (6, 8)); |
| 2546 | /// ``` |
| 2547 | #[unstable(feature = "signed_bigint_helpers" , issue = "151989" )] |
| 2548 | #[must_use = "this returns the result of the operation, \ |
| 2549 | without modifying the original" ] |
| 2550 | #[inline] |
| 2551 | pub const fn carrying_add(self, rhs: Self, carry: bool) -> (Self, bool) { |
| 2552 | // note: longer-term this should be done via an intrinsic. |
| 2553 | // note: no intermediate overflow is required (https://github.com/rust-lang/rust/issues/85532#issuecomment-1032214946). |
| 2554 | let (a, b) = self.overflowing_add(rhs); |
| 2555 | let (c, d) = a.overflowing_add(carry as $SelfT); |
| 2556 | (c, b != d) |
| 2557 | } |
| 2558 | |
| 2559 | /// Calculates `self` + `rhs` with an unsigned `rhs`. |
| 2560 | /// |
| 2561 | /// Returns a tuple of the addition along with a boolean indicating |
| 2562 | /// whether an arithmetic overflow would occur. If an overflow would |
| 2563 | /// have occurred then the wrapped value is returned. |
| 2564 | /// |
| 2565 | /// # Examples |
| 2566 | /// |
| 2567 | /// ``` |
| 2568 | #[doc = concat!("assert_eq!(1" , stringify!($SelfT), ".overflowing_add_unsigned(2), (3, false));" )] |
| 2569 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MIN).overflowing_add_unsigned(" , stringify!($UnsignedT), "::MAX), (" , stringify!($SelfT), "::MAX, false));" )] |
| 2570 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MAX - 2).overflowing_add_unsigned(3), (" , stringify!($SelfT), "::MIN, true));" )] |
| 2571 | /// ``` |
| 2572 | #[stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 2573 | #[rustc_const_stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 2574 | #[must_use = "this returns the result of the operation, \ |
| 2575 | without modifying the original" ] |
| 2576 | #[inline] |
| 2577 | pub const fn overflowing_add_unsigned(self, rhs: $UnsignedT) -> (Self, bool) { |
| 2578 | let rhs = rhs as Self; |
| 2579 | let (res, overflowed) = self.overflowing_add(rhs); |
| 2580 | (res, overflowed ^ (rhs < 0)) |
| 2581 | } |
| 2582 | |
| 2583 | /// Calculates `self` - `rhs`. |
| 2584 | /// |
| 2585 | /// Returns a tuple of the subtraction along with a boolean indicating whether an arithmetic overflow |
| 2586 | /// would occur. If an overflow would have occurred then the wrapped value is returned. |
| 2587 | /// |
| 2588 | /// # Examples |
| 2589 | /// |
| 2590 | /// ``` |
| 2591 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".overflowing_sub(2), (3, false));" )] |
| 2592 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.overflowing_sub(1), (" , stringify!($SelfT), "::MAX, true));" )] |
| 2593 | /// ``` |
| 2594 | #[stable(feature = "wrapping" , since = "1.7.0" )] |
| 2595 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 2596 | #[must_use = "this returns the result of the operation, \ |
| 2597 | without modifying the original" ] |
| 2598 | #[inline(always)] |
| 2599 | pub const fn overflowing_sub(self, rhs: Self) -> (Self, bool) { |
| 2600 | let (a, b) = intrinsics::sub_with_overflow(self as $ActualT, rhs as $ActualT); |
| 2601 | (a as Self, b) |
| 2602 | } |
| 2603 | |
| 2604 | /// Calculates `self` − `rhs` − `borrow` and checks for |
| 2605 | /// overflow. |
| 2606 | /// |
| 2607 | /// Performs "ternary subtraction" by subtracting both an integer |
| 2608 | /// operand and a borrow-in bit from `self`, and returns a tuple of the |
| 2609 | /// difference along with a boolean indicating whether an arithmetic |
| 2610 | /// overflow would occur. On overflow, the wrapped value is returned. |
| 2611 | /// |
| 2612 | /// This allows chaining together multiple subtractions to create a |
| 2613 | /// wider subtraction, and can be useful for bignum subtraction. This |
| 2614 | /// method should only be used for the most significant word; for the |
| 2615 | /// less significant words the unsigned method |
| 2616 | #[doc = concat!("[`" , stringify!($UnsignedT), "::borrowing_sub`]" )] |
| 2617 | /// should be used. |
| 2618 | /// |
| 2619 | /// The output boolean returned by this method is *not* a borrow flag, |
| 2620 | /// and should *not* be subtracted from a more significant word. |
| 2621 | /// |
| 2622 | /// If the input borrow is false, this method is equivalent to |
| 2623 | /// [`overflowing_sub`](Self::overflowing_sub). |
| 2624 | /// |
| 2625 | /// # Examples |
| 2626 | /// |
| 2627 | /// ``` |
| 2628 | /// #![feature(signed_bigint_helpers)] |
| 2629 | /// // Only the most significant word is signed. |
| 2630 | /// // |
| 2631 | #[doc = concat!("// 6 8 (a = 6 × 2^" , stringify!($BITS), " + 8)" )] |
| 2632 | #[doc = concat!("// - -5 9 (b = -5 × 2^" , stringify!($BITS), " + 9)" )] |
| 2633 | /// // --------- |
| 2634 | #[doc = concat!("// 10 MAX (diff = 10 × 2^" , stringify!($BITS), " + 2^" , stringify!($BITS), " - 1)" )] |
| 2635 | /// |
| 2636 | #[doc = concat!("let (a1, a0): (" , stringify!($SelfT), ", " , stringify!($UnsignedT), ") = (6, 8);" )] |
| 2637 | #[doc = concat!("let (b1, b0): (" , stringify!($SelfT), ", " , stringify!($UnsignedT), ") = (-5, 9);" )] |
| 2638 | /// let borrow0 = false; |
| 2639 | /// |
| 2640 | #[doc = concat!("// " , stringify!($UnsignedT), "::borrowing_sub for the less significant words" )] |
| 2641 | /// let (diff0, borrow1) = a0.borrowing_sub(b0, borrow0); |
| 2642 | /// assert_eq!(borrow1, true); |
| 2643 | /// |
| 2644 | #[doc = concat!("// " , stringify!($SelfT), "::borrowing_sub for the most significant word" )] |
| 2645 | /// let (diff1, overflow) = a1.borrowing_sub(b1, borrow1); |
| 2646 | /// assert_eq!(overflow, false); |
| 2647 | /// |
| 2648 | #[doc = concat!("assert_eq!((diff1, diff0), (10, " , stringify!($UnsignedT), "::MAX));" )] |
| 2649 | /// ``` |
| 2650 | #[unstable(feature = "signed_bigint_helpers" , issue = "151989" )] |
| 2651 | #[must_use = "this returns the result of the operation, \ |
| 2652 | without modifying the original" ] |
| 2653 | #[inline] |
| 2654 | pub const fn borrowing_sub(self, rhs: Self, borrow: bool) -> (Self, bool) { |
| 2655 | // note: longer-term this should be done via an intrinsic. |
| 2656 | // note: no intermediate overflow is required (https://github.com/rust-lang/rust/issues/85532#issuecomment-1032214946). |
| 2657 | let (a, b) = self.overflowing_sub(rhs); |
| 2658 | let (c, d) = a.overflowing_sub(borrow as $SelfT); |
| 2659 | (c, b != d) |
| 2660 | } |
| 2661 | |
| 2662 | /// Calculates `self` - `rhs` with an unsigned `rhs`. |
| 2663 | /// |
| 2664 | /// Returns a tuple of the subtraction along with a boolean indicating |
| 2665 | /// whether an arithmetic overflow would occur. If an overflow would |
| 2666 | /// have occurred then the wrapped value is returned. |
| 2667 | /// |
| 2668 | /// # Examples |
| 2669 | /// |
| 2670 | /// ``` |
| 2671 | #[doc = concat!("assert_eq!(1" , stringify!($SelfT), ".overflowing_sub_unsigned(2), (-1, false));" )] |
| 2672 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MAX).overflowing_sub_unsigned(" , stringify!($UnsignedT), "::MAX), (" , stringify!($SelfT), "::MIN, false));" )] |
| 2673 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MIN + 2).overflowing_sub_unsigned(3), (" , stringify!($SelfT), "::MAX, true));" )] |
| 2674 | /// ``` |
| 2675 | #[stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 2676 | #[rustc_const_stable(feature = "mixed_integer_ops" , since = "1.66.0" )] |
| 2677 | #[must_use = "this returns the result of the operation, \ |
| 2678 | without modifying the original" ] |
| 2679 | #[inline] |
| 2680 | pub const fn overflowing_sub_unsigned(self, rhs: $UnsignedT) -> (Self, bool) { |
| 2681 | let rhs = rhs as Self; |
| 2682 | let (res, overflowed) = self.overflowing_sub(rhs); |
| 2683 | (res, overflowed ^ (rhs < 0)) |
| 2684 | } |
| 2685 | |
| 2686 | /// Calculates the multiplication of `self` and `rhs`. |
| 2687 | /// |
| 2688 | /// Returns a tuple of the multiplication along with a boolean indicating whether an arithmetic overflow |
| 2689 | /// would occur. If an overflow would have occurred then the wrapped value is returned. |
| 2690 | /// |
| 2691 | /// # Examples |
| 2692 | /// |
| 2693 | /// ``` |
| 2694 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".overflowing_mul(2), (10, false));" )] |
| 2695 | /// assert_eq!(1_000_000_000i32.overflowing_mul(10), (1410065408, true)); |
| 2696 | /// ``` |
| 2697 | #[stable(feature = "wrapping" , since = "1.7.0" )] |
| 2698 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 2699 | #[must_use = "this returns the result of the operation, \ |
| 2700 | without modifying the original" ] |
| 2701 | #[inline(always)] |
| 2702 | pub const fn overflowing_mul(self, rhs: Self) -> (Self, bool) { |
| 2703 | let (a, b) = intrinsics::mul_with_overflow(self as $ActualT, rhs as $ActualT); |
| 2704 | (a as Self, b) |
| 2705 | } |
| 2706 | |
| 2707 | /// Calculates the complete product `self * rhs` without the possibility to overflow. |
| 2708 | /// |
| 2709 | /// This returns the low-order (wrapping) bits and the high-order (overflow) bits |
| 2710 | /// of the result as two separate values, in that order. |
| 2711 | /// |
| 2712 | /// If you also need to add a carry to the wide result, then you want |
| 2713 | /// [`Self::carrying_mul`] instead. |
| 2714 | /// |
| 2715 | /// # Examples |
| 2716 | /// |
| 2717 | /// Please note that this example is shared among integer types, which is why `i32` is used. |
| 2718 | /// |
| 2719 | /// ``` |
| 2720 | /// #![feature(widening_mul)] |
| 2721 | /// assert_eq!(5i32.widening_mul(-2), (4294967286, -1)); |
| 2722 | /// assert_eq!(1_000_000_000i32.widening_mul(-10), (2884901888, -3)); |
| 2723 | /// ``` |
| 2724 | #[unstable(feature = "widening_mul" , issue = "152016" )] |
| 2725 | #[rustc_const_unstable(feature = "widening_mul" , issue = "152016" )] |
| 2726 | #[must_use = "this returns the result of the operation, \ |
| 2727 | without modifying the original" ] |
| 2728 | #[inline] |
| 2729 | pub const fn widening_mul(self, rhs: Self) -> ($UnsignedT, Self) { |
| 2730 | Self::carrying_mul_add(self, rhs, 0, 0) |
| 2731 | } |
| 2732 | |
| 2733 | /// Calculates the "full multiplication" `self * rhs + carry` |
| 2734 | /// without the possibility to overflow. |
| 2735 | /// |
| 2736 | /// This returns the low-order (wrapping) bits and the high-order (overflow) bits |
| 2737 | /// of the result as two separate values, in that order. |
| 2738 | /// |
| 2739 | /// Performs "long multiplication" which takes in an extra amount to add, and may return an |
| 2740 | /// additional amount of overflow. This allows for chaining together multiple |
| 2741 | /// multiplications to create "big integers" which represent larger values. |
| 2742 | /// |
| 2743 | /// If you don't need the `carry`, then you can use [`Self::widening_mul`] instead. |
| 2744 | /// |
| 2745 | /// # Examples |
| 2746 | /// |
| 2747 | /// Please note that this example is shared among integer types, which is why `i32` is used. |
| 2748 | /// |
| 2749 | /// ``` |
| 2750 | /// #![feature(signed_bigint_helpers)] |
| 2751 | /// assert_eq!(5i32.carrying_mul(-2, 0), (4294967286, -1)); |
| 2752 | /// assert_eq!(5i32.carrying_mul(-2, 10), (0, 0)); |
| 2753 | /// assert_eq!(1_000_000_000i32.carrying_mul(-10, 0), (2884901888, -3)); |
| 2754 | /// assert_eq!(1_000_000_000i32.carrying_mul(-10, 10), (2884901898, -3)); |
| 2755 | #[doc = concat!("assert_eq!(" , |
| 2756 | stringify!($SelfT), "::MAX.carrying_mul(" , stringify!($SelfT), "::MAX, " , stringify!($SelfT), "::MAX), " , |
| 2757 | "(" , stringify!($SelfT), "::MAX.unsigned_abs() + 1, " , stringify!($SelfT), "::MAX / 2));" |
| 2758 | )] |
| 2759 | /// ``` |
| 2760 | #[unstable(feature = "signed_bigint_helpers" , issue = "151989" )] |
| 2761 | #[rustc_const_unstable(feature = "signed_bigint_helpers" , issue = "151989" )] |
| 2762 | #[must_use = "this returns the result of the operation, \ |
| 2763 | without modifying the original" ] |
| 2764 | #[inline] |
| 2765 | pub const fn carrying_mul(self, rhs: Self, carry: Self) -> ($UnsignedT, Self) { |
| 2766 | Self::carrying_mul_add(self, rhs, carry, 0) |
| 2767 | } |
| 2768 | |
| 2769 | /// Calculates the "full multiplication" `self * rhs + carry + add` |
| 2770 | /// without the possibility to overflow. |
| 2771 | /// |
| 2772 | /// This returns the low-order (wrapping) bits and the high-order (overflow) bits |
| 2773 | /// of the result as two separate values, in that order. |
| 2774 | /// |
| 2775 | /// Performs "long multiplication" which takes in an extra amount to add, and may return an |
| 2776 | /// additional amount of overflow. This allows for chaining together multiple |
| 2777 | /// multiplications to create "big integers" which represent larger values. |
| 2778 | /// |
| 2779 | /// If you don't need either `carry`, then you can use [`Self::widening_mul`] instead, |
| 2780 | /// and if you only need one `carry`, then you can use [`Self::carrying_mul`] instead. |
| 2781 | /// |
| 2782 | /// # Examples |
| 2783 | /// |
| 2784 | /// Please note that this example is shared among integer types, which is why `i32` is used. |
| 2785 | /// |
| 2786 | /// ``` |
| 2787 | /// #![feature(signed_bigint_helpers)] |
| 2788 | /// assert_eq!(5i32.carrying_mul_add(-2, 0, 0), (4294967286, -1)); |
| 2789 | /// assert_eq!(5i32.carrying_mul_add(-2, 10, 10), (10, 0)); |
| 2790 | /// assert_eq!(1_000_000_000i32.carrying_mul_add(-10, 0, 0), (2884901888, -3)); |
| 2791 | /// assert_eq!(1_000_000_000i32.carrying_mul_add(-10, 10, 10), (2884901908, -3)); |
| 2792 | #[doc = concat!("assert_eq!(" , |
| 2793 | stringify!($SelfT), "::MAX.carrying_mul_add(" , stringify!($SelfT), "::MAX, " , stringify!($SelfT), "::MAX, " , stringify!($SelfT), "::MAX), " , |
| 2794 | "(" , stringify!($UnsignedT), "::MAX, " , stringify!($SelfT), "::MAX / 2));" |
| 2795 | )] |
| 2796 | /// ``` |
| 2797 | #[unstable(feature = "signed_bigint_helpers" , issue = "151989" )] |
| 2798 | #[rustc_const_unstable(feature = "signed_bigint_helpers" , issue = "151989" )] |
| 2799 | #[must_use = "this returns the result of the operation, \ |
| 2800 | without modifying the original" ] |
| 2801 | #[inline] |
| 2802 | pub const fn carrying_mul_add(self, rhs: Self, carry: Self, add: Self) -> ($UnsignedT, Self) { |
| 2803 | intrinsics::carrying_mul_add(self, rhs, carry, add) |
| 2804 | } |
| 2805 | |
| 2806 | /// Calculates the divisor when `self` is divided by `rhs`. |
| 2807 | /// |
| 2808 | /// Returns a tuple of the divisor along with a boolean indicating whether an arithmetic overflow would |
| 2809 | /// occur. If an overflow would occur then self is returned. |
| 2810 | /// |
| 2811 | /// # Panics |
| 2812 | /// |
| 2813 | /// This function will panic if `rhs` is zero. |
| 2814 | /// |
| 2815 | /// # Examples |
| 2816 | /// |
| 2817 | /// ``` |
| 2818 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".overflowing_div(2), (2, false));" )] |
| 2819 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.overflowing_div(-1), (" , stringify!($SelfT), "::MIN, true));" )] |
| 2820 | /// ``` |
| 2821 | #[inline] |
| 2822 | #[stable(feature = "wrapping" , since = "1.7.0" )] |
| 2823 | #[rustc_const_stable(feature = "const_overflowing_int_methods" , since = "1.52.0" )] |
| 2824 | #[must_use = "this returns the result of the operation, \ |
| 2825 | without modifying the original" ] |
| 2826 | pub const fn overflowing_div(self, rhs: Self) -> (Self, bool) { |
| 2827 | // Using `&` helps LLVM see that it is the same check made in division. |
| 2828 | if intrinsics::unlikely((self == Self::MIN) & (rhs == -1)) { |
| 2829 | (self, true) |
| 2830 | } else { |
| 2831 | (self / rhs, false) |
| 2832 | } |
| 2833 | } |
| 2834 | |
| 2835 | /// Calculates the quotient of Euclidean division `self.div_euclid(rhs)`. |
| 2836 | /// |
| 2837 | /// Returns a tuple of the divisor along with a boolean indicating whether an arithmetic overflow would |
| 2838 | /// occur. If an overflow would occur then `self` is returned. |
| 2839 | /// |
| 2840 | /// # Panics |
| 2841 | /// |
| 2842 | /// This function will panic if `rhs` is zero. |
| 2843 | /// |
| 2844 | /// # Examples |
| 2845 | /// |
| 2846 | /// ``` |
| 2847 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".overflowing_div_euclid(2), (2, false));" )] |
| 2848 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.overflowing_div_euclid(-1), (" , stringify!($SelfT), "::MIN, true));" )] |
| 2849 | /// ``` |
| 2850 | #[inline] |
| 2851 | #[stable(feature = "euclidean_division" , since = "1.38.0" )] |
| 2852 | #[rustc_const_stable(feature = "const_euclidean_int_methods" , since = "1.52.0" )] |
| 2853 | #[must_use = "this returns the result of the operation, \ |
| 2854 | without modifying the original" ] |
| 2855 | pub const fn overflowing_div_euclid(self, rhs: Self) -> (Self, bool) { |
| 2856 | // Using `&` helps LLVM see that it is the same check made in division. |
| 2857 | if intrinsics::unlikely((self == Self::MIN) & (rhs == -1)) { |
| 2858 | (self, true) |
| 2859 | } else { |
| 2860 | (self.div_euclid(rhs), false) |
| 2861 | } |
| 2862 | } |
| 2863 | |
| 2864 | /// Calculates the remainder when `self` is divided by `rhs`. |
| 2865 | /// |
| 2866 | /// Returns a tuple of the remainder after dividing along with a boolean indicating whether an |
| 2867 | /// arithmetic overflow would occur. If an overflow would occur then 0 is returned. |
| 2868 | /// |
| 2869 | /// # Panics |
| 2870 | /// |
| 2871 | /// This function will panic if `rhs` is zero. |
| 2872 | /// |
| 2873 | /// # Examples |
| 2874 | /// |
| 2875 | /// ``` |
| 2876 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".overflowing_rem(2), (1, false));" )] |
| 2877 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.overflowing_rem(-1), (0, true));" )] |
| 2878 | /// ``` |
| 2879 | #[inline] |
| 2880 | #[stable(feature = "wrapping" , since = "1.7.0" )] |
| 2881 | #[rustc_const_stable(feature = "const_overflowing_int_methods" , since = "1.52.0" )] |
| 2882 | #[must_use = "this returns the result of the operation, \ |
| 2883 | without modifying the original" ] |
| 2884 | pub const fn overflowing_rem(self, rhs: Self) -> (Self, bool) { |
| 2885 | if intrinsics::unlikely(rhs == -1) { |
| 2886 | (0, self == Self::MIN) |
| 2887 | } else { |
| 2888 | (self % rhs, false) |
| 2889 | } |
| 2890 | } |
| 2891 | |
| 2892 | |
| 2893 | /// Overflowing Euclidean remainder. Calculates `self.rem_euclid(rhs)`. |
| 2894 | /// |
| 2895 | /// Returns a tuple of the remainder after dividing along with a boolean indicating whether an |
| 2896 | /// arithmetic overflow would occur. If an overflow would occur then 0 is returned. |
| 2897 | /// |
| 2898 | /// # Panics |
| 2899 | /// |
| 2900 | /// This function will panic if `rhs` is zero. |
| 2901 | /// |
| 2902 | /// # Examples |
| 2903 | /// |
| 2904 | /// ``` |
| 2905 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".overflowing_rem_euclid(2), (1, false));" )] |
| 2906 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.overflowing_rem_euclid(-1), (0, true));" )] |
| 2907 | /// ``` |
| 2908 | #[stable(feature = "euclidean_division" , since = "1.38.0" )] |
| 2909 | #[rustc_const_stable(feature = "const_euclidean_int_methods" , since = "1.52.0" )] |
| 2910 | #[must_use = "this returns the result of the operation, \ |
| 2911 | without modifying the original" ] |
| 2912 | #[inline] |
| 2913 | #[track_caller] |
| 2914 | pub const fn overflowing_rem_euclid(self, rhs: Self) -> (Self, bool) { |
| 2915 | if intrinsics::unlikely(rhs == -1) { |
| 2916 | (0, self == Self::MIN) |
| 2917 | } else { |
| 2918 | (self.rem_euclid(rhs), false) |
| 2919 | } |
| 2920 | } |
| 2921 | |
| 2922 | |
| 2923 | /// Negates self, overflowing if this is equal to the minimum value. |
| 2924 | /// |
| 2925 | /// Returns a tuple of the negated version of self along with a boolean indicating whether an overflow |
| 2926 | /// happened. If `self` is the minimum value (e.g., `i32::MIN` for values of type `i32`), then the |
| 2927 | /// minimum value will be returned again and `true` will be returned for an overflow happening. |
| 2928 | /// |
| 2929 | /// # Examples |
| 2930 | /// |
| 2931 | /// ``` |
| 2932 | #[doc = concat!("assert_eq!(2" , stringify!($SelfT), ".overflowing_neg(), (-2, false));" )] |
| 2933 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.overflowing_neg(), (" , stringify!($SelfT), "::MIN, true));" )] |
| 2934 | /// ``` |
| 2935 | #[inline] |
| 2936 | #[stable(feature = "wrapping" , since = "1.7.0" )] |
| 2937 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 2938 | #[must_use = "this returns the result of the operation, \ |
| 2939 | without modifying the original" ] |
| 2940 | #[allow(unused_attributes)] |
| 2941 | pub const fn overflowing_neg(self) -> (Self, bool) { |
| 2942 | if intrinsics::unlikely(self == Self::MIN) { |
| 2943 | (Self::MIN, true) |
| 2944 | } else { |
| 2945 | (-self, false) |
| 2946 | } |
| 2947 | } |
| 2948 | |
| 2949 | /// Shifts self left by `rhs` bits. |
| 2950 | /// |
| 2951 | /// Returns a tuple of the shifted version of self along with a boolean indicating whether the shift |
| 2952 | /// value was larger than or equal to the number of bits. If the shift value is too large, then value is |
| 2953 | /// masked (N-1) where N is the number of bits, and this value is then used to perform the shift. |
| 2954 | /// |
| 2955 | /// # Examples |
| 2956 | /// |
| 2957 | /// ``` |
| 2958 | #[doc = concat!("assert_eq!(0x1" , stringify!($SelfT),".overflowing_shl(4), (0x10, false));" )] |
| 2959 | /// assert_eq!(0x1i32.overflowing_shl(36), (0x10, true)); |
| 2960 | #[doc = concat!("assert_eq!(0x10" , stringify!($SelfT), ".overflowing_shl(" , stringify!($BITS_MINUS_ONE), "), (0, false));" )] |
| 2961 | /// ``` |
| 2962 | #[stable(feature = "wrapping" , since = "1.7.0" )] |
| 2963 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 2964 | #[must_use = "this returns the result of the operation, \ |
| 2965 | without modifying the original" ] |
| 2966 | #[inline] |
| 2967 | pub const fn overflowing_shl(self, rhs: u32) -> (Self, bool) { |
| 2968 | (self.wrapping_shl(rhs), rhs >= Self::BITS) |
| 2969 | } |
| 2970 | |
| 2971 | /// Shifts self right by `rhs` bits. |
| 2972 | /// |
| 2973 | /// Returns a tuple of the shifted version of self along with a boolean indicating whether the shift |
| 2974 | /// value was larger than or equal to the number of bits. If the shift value is too large, then value is |
| 2975 | /// masked (N-1) where N is the number of bits, and this value is then used to perform the shift. |
| 2976 | /// |
| 2977 | /// # Examples |
| 2978 | /// |
| 2979 | /// ``` |
| 2980 | #[doc = concat!("assert_eq!(0x10" , stringify!($SelfT), ".overflowing_shr(4), (0x1, false));" )] |
| 2981 | /// assert_eq!(0x10i32.overflowing_shr(36), (0x1, true)); |
| 2982 | /// ``` |
| 2983 | #[stable(feature = "wrapping" , since = "1.7.0" )] |
| 2984 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 2985 | #[must_use = "this returns the result of the operation, \ |
| 2986 | without modifying the original" ] |
| 2987 | #[inline] |
| 2988 | pub const fn overflowing_shr(self, rhs: u32) -> (Self, bool) { |
| 2989 | (self.wrapping_shr(rhs), rhs >= Self::BITS) |
| 2990 | } |
| 2991 | |
| 2992 | /// Computes the absolute value of `self`. |
| 2993 | /// |
| 2994 | /// Returns a tuple of the absolute version of self along with a boolean indicating whether an overflow |
| 2995 | /// happened. If self is the minimum value |
| 2996 | #[doc = concat!("(e.g., " , stringify!($SelfT), "::MIN for values of type " , stringify!($SelfT), ")," )] |
| 2997 | /// then the minimum value will be returned again and true will be returned |
| 2998 | /// for an overflow happening. |
| 2999 | /// |
| 3000 | /// # Examples |
| 3001 | /// |
| 3002 | /// ``` |
| 3003 | #[doc = concat!("assert_eq!(10" , stringify!($SelfT), ".overflowing_abs(), (10, false));" )] |
| 3004 | #[doc = concat!("assert_eq!((-10" , stringify!($SelfT), ").overflowing_abs(), (10, false));" )] |
| 3005 | #[doc = concat!("assert_eq!((" , stringify!($SelfT), "::MIN).overflowing_abs(), (" , stringify!($SelfT), "::MIN, true));" )] |
| 3006 | /// ``` |
| 3007 | #[stable(feature = "no_panic_abs" , since = "1.13.0" )] |
| 3008 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 3009 | #[must_use = "this returns the result of the operation, \ |
| 3010 | without modifying the original" ] |
| 3011 | #[inline] |
| 3012 | pub const fn overflowing_abs(self) -> (Self, bool) { |
| 3013 | (self.wrapping_abs(), self == Self::MIN) |
| 3014 | } |
| 3015 | |
| 3016 | /// Raises self to the power of `exp`, using exponentiation by squaring. |
| 3017 | /// |
| 3018 | /// Returns a tuple of the exponentiation along with a bool indicating |
| 3019 | /// whether an overflow happened. |
| 3020 | /// |
| 3021 | /// # Examples |
| 3022 | /// |
| 3023 | /// ``` |
| 3024 | #[doc = concat!("assert_eq!(3" , stringify!($SelfT), ".overflowing_pow(4), (81, false));" )] |
| 3025 | #[doc = concat!("assert_eq!(0_" , stringify!($SelfT), ".overflowing_pow(0), (1, false));" )] |
| 3026 | /// assert_eq!(3i8.overflowing_pow(5), (-13, true)); |
| 3027 | /// ``` |
| 3028 | #[stable(feature = "no_panic_pow" , since = "1.34.0" )] |
| 3029 | #[rustc_const_stable(feature = "const_int_pow" , since = "1.50.0" )] |
| 3030 | #[must_use = "this returns the result of the operation, \ |
| 3031 | without modifying the original" ] |
| 3032 | #[inline] |
| 3033 | pub const fn overflowing_pow(self, mut exp: u32) -> (Self, bool) { |
| 3034 | if exp == 0 { |
| 3035 | return (1,false); |
| 3036 | } |
| 3037 | let mut base = self; |
| 3038 | let mut acc: Self = 1; |
| 3039 | let mut overflown = false; |
| 3040 | // Scratch space for storing results of overflowing_mul. |
| 3041 | let mut r; |
| 3042 | |
| 3043 | loop { |
| 3044 | if (exp & 1) == 1 { |
| 3045 | r = acc.overflowing_mul(base); |
| 3046 | // since exp!=0, finally the exp must be 1. |
| 3047 | if exp == 1 { |
| 3048 | r.1 |= overflown; |
| 3049 | return r; |
| 3050 | } |
| 3051 | acc = r.0; |
| 3052 | overflown |= r.1; |
| 3053 | } |
| 3054 | exp /= 2; |
| 3055 | r = base.overflowing_mul(base); |
| 3056 | base = r.0; |
| 3057 | overflown |= r.1; |
| 3058 | } |
| 3059 | } |
| 3060 | |
| 3061 | /// Raises self to the power of `exp`, using exponentiation by squaring. |
| 3062 | /// |
| 3063 | /// # Examples |
| 3064 | /// |
| 3065 | /// ``` |
| 3066 | #[doc = concat!("let x: " , stringify!($SelfT), " = 2; // or any other integer type" )] |
| 3067 | /// |
| 3068 | /// assert_eq!(x.pow(5), 32); |
| 3069 | #[doc = concat!("assert_eq!(0_" , stringify!($SelfT), ".pow(0), 1);" )] |
| 3070 | /// ``` |
| 3071 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 3072 | #[rustc_const_stable(feature = "const_int_pow" , since = "1.50.0" )] |
| 3073 | #[must_use = "this returns the result of the operation, \ |
| 3074 | without modifying the original" ] |
| 3075 | #[inline] |
| 3076 | #[rustc_inherit_overflow_checks] |
| 3077 | pub const fn pow(self, mut exp: u32) -> Self { |
| 3078 | if exp == 0 { |
| 3079 | return 1; |
| 3080 | } |
| 3081 | let mut base = self; |
| 3082 | let mut acc = 1; |
| 3083 | |
| 3084 | if intrinsics::is_val_statically_known(exp) { |
| 3085 | while exp > 1 { |
| 3086 | if (exp & 1) == 1 { |
| 3087 | acc = acc * base; |
| 3088 | } |
| 3089 | exp /= 2; |
| 3090 | base = base * base; |
| 3091 | } |
| 3092 | |
| 3093 | // since exp!=0, finally the exp must be 1. |
| 3094 | // Deal with the final bit of the exponent separately, since |
| 3095 | // squaring the base afterwards is not necessary and may cause a |
| 3096 | // needless overflow. |
| 3097 | acc * base |
| 3098 | } else { |
| 3099 | // This is faster than the above when the exponent is not known |
| 3100 | // at compile time. We can't use the same code for the constant |
| 3101 | // exponent case because LLVM is currently unable to unroll |
| 3102 | // this loop. |
| 3103 | loop { |
| 3104 | if (exp & 1) == 1 { |
| 3105 | acc = acc * base; |
| 3106 | // since exp!=0, finally the exp must be 1. |
| 3107 | if exp == 1 { |
| 3108 | return acc; |
| 3109 | } |
| 3110 | } |
| 3111 | exp /= 2; |
| 3112 | base = base * base; |
| 3113 | } |
| 3114 | } |
| 3115 | } |
| 3116 | |
| 3117 | /// Returns the square root of the number, rounded down. |
| 3118 | /// |
| 3119 | /// # Panics |
| 3120 | /// |
| 3121 | /// This function will panic if `self` is negative. |
| 3122 | /// |
| 3123 | /// # Examples |
| 3124 | /// |
| 3125 | /// ``` |
| 3126 | #[doc = concat!("assert_eq!(10" , stringify!($SelfT), ".isqrt(), 3);" )] |
| 3127 | /// ``` |
| 3128 | #[stable(feature = "isqrt" , since = "1.84.0" )] |
| 3129 | #[rustc_const_stable(feature = "isqrt" , since = "1.84.0" )] |
| 3130 | #[must_use = "this returns the result of the operation, \ |
| 3131 | without modifying the original" ] |
| 3132 | #[inline] |
| 3133 | #[track_caller] |
| 3134 | pub const fn isqrt(self) -> Self { |
| 3135 | match self.checked_isqrt() { |
| 3136 | Some(sqrt) => sqrt, |
| 3137 | None => crate::num::int_sqrt::panic_for_negative_argument(), |
| 3138 | } |
| 3139 | } |
| 3140 | |
| 3141 | /// Calculates the quotient of Euclidean division of `self` by `rhs`. |
| 3142 | /// |
| 3143 | /// This computes the integer `q` such that `self = q * rhs + r`, with |
| 3144 | /// `r = self.rem_euclid(rhs)` and `0 <= r < abs(rhs)`. |
| 3145 | /// |
| 3146 | /// In other words, the result is `self / rhs` rounded to the integer `q` |
| 3147 | /// such that `self >= q * rhs`. |
| 3148 | /// If `self > 0`, this is equal to rounding towards zero (the default in Rust); |
| 3149 | /// if `self < 0`, this is equal to rounding away from zero (towards +/- infinity). |
| 3150 | /// If `rhs > 0`, this is equal to rounding towards -infinity; |
| 3151 | /// if `rhs < 0`, this is equal to rounding towards +infinity. |
| 3152 | /// |
| 3153 | /// # Panics |
| 3154 | /// |
| 3155 | /// This function will panic if `rhs` is zero or if `self` is `Self::MIN` |
| 3156 | /// and `rhs` is -1. This behavior is not affected by the `overflow-checks` flag. |
| 3157 | /// |
| 3158 | /// # Examples |
| 3159 | /// |
| 3160 | /// ``` |
| 3161 | #[doc = concat!("let a: " , stringify!($SelfT), " = 7; // or any other integer type" )] |
| 3162 | /// let b = 4; |
| 3163 | /// |
| 3164 | /// assert_eq!(a.div_euclid(b), 1); // 7 >= 4 * 1 |
| 3165 | /// assert_eq!(a.div_euclid(-b), -1); // 7 >= -4 * -1 |
| 3166 | /// assert_eq!((-a).div_euclid(b), -2); // -7 >= 4 * -2 |
| 3167 | /// assert_eq!((-a).div_euclid(-b), 2); // -7 >= -4 * 2 |
| 3168 | /// ``` |
| 3169 | #[stable(feature = "euclidean_division" , since = "1.38.0" )] |
| 3170 | #[rustc_const_stable(feature = "const_euclidean_int_methods" , since = "1.52.0" )] |
| 3171 | #[must_use = "this returns the result of the operation, \ |
| 3172 | without modifying the original" ] |
| 3173 | #[inline] |
| 3174 | #[track_caller] |
| 3175 | pub const fn div_euclid(self, rhs: Self) -> Self { |
| 3176 | let q = self / rhs; |
| 3177 | if self % rhs < 0 { |
| 3178 | return if rhs > 0 { q - 1 } else { q + 1 } |
| 3179 | } |
| 3180 | q |
| 3181 | } |
| 3182 | |
| 3183 | |
| 3184 | /// Calculates the least nonnegative remainder of `self` when |
| 3185 | /// divided by `rhs`. |
| 3186 | /// |
| 3187 | /// This is done as if by the Euclidean division algorithm -- given |
| 3188 | /// `r = self.rem_euclid(rhs)`, the result satisfies |
| 3189 | /// `self = rhs * self.div_euclid(rhs) + r` and `0 <= r < abs(rhs)`. |
| 3190 | /// |
| 3191 | /// # Panics |
| 3192 | /// |
| 3193 | /// This function will panic if `rhs` is zero or if `self` is `Self::MIN` and |
| 3194 | /// `rhs` is -1. This behavior is not affected by the `overflow-checks` flag. |
| 3195 | /// |
| 3196 | /// # Examples |
| 3197 | /// |
| 3198 | /// ``` |
| 3199 | #[doc = concat!("let a: " , stringify!($SelfT), " = 7; // or any other integer type" )] |
| 3200 | /// let b = 4; |
| 3201 | /// |
| 3202 | /// assert_eq!(a.rem_euclid(b), 3); |
| 3203 | /// assert_eq!((-a).rem_euclid(b), 1); |
| 3204 | /// assert_eq!(a.rem_euclid(-b), 3); |
| 3205 | /// assert_eq!((-a).rem_euclid(-b), 1); |
| 3206 | /// ``` |
| 3207 | /// |
| 3208 | /// This will panic: |
| 3209 | /// ```should_panic |
| 3210 | #[doc = concat!("let _ = " , stringify!($SelfT), "::MIN.rem_euclid(-1);" )] |
| 3211 | /// ``` |
| 3212 | #[doc(alias = "modulo" , alias = "mod" )] |
| 3213 | #[stable(feature = "euclidean_division" , since = "1.38.0" )] |
| 3214 | #[rustc_const_stable(feature = "const_euclidean_int_methods" , since = "1.52.0" )] |
| 3215 | #[must_use = "this returns the result of the operation, \ |
| 3216 | without modifying the original" ] |
| 3217 | #[inline] |
| 3218 | #[track_caller] |
| 3219 | pub const fn rem_euclid(self, rhs: Self) -> Self { |
| 3220 | let r = self % rhs; |
| 3221 | if r < 0 { |
| 3222 | // Semantically equivalent to `if rhs < 0 { r - rhs } else { r + rhs }`. |
| 3223 | // If `rhs` is not `Self::MIN`, then `r + abs(rhs)` will not overflow |
| 3224 | // and is clearly equivalent, because `r` is negative. |
| 3225 | // Otherwise, `rhs` is `Self::MIN`, then we have |
| 3226 | // `r.wrapping_add(Self::MIN.wrapping_abs())`, which evaluates |
| 3227 | // to `r.wrapping_add(Self::MIN)`, which is equivalent to |
| 3228 | // `r - Self::MIN`, which is what we wanted (and will not overflow |
| 3229 | // for negative `r`). |
| 3230 | r.wrapping_add(rhs.wrapping_abs()) |
| 3231 | } else { |
| 3232 | r |
| 3233 | } |
| 3234 | } |
| 3235 | |
| 3236 | /// Calculates the quotient of `self` and `rhs`, rounding the result towards negative infinity. |
| 3237 | /// |
| 3238 | /// # Panics |
| 3239 | /// |
| 3240 | /// This function will panic if `rhs` is zero or if `self` is `Self::MIN` |
| 3241 | /// and `rhs` is -1. This behavior is not affected by the `overflow-checks` flag. |
| 3242 | /// |
| 3243 | /// # Examples |
| 3244 | /// |
| 3245 | /// ``` |
| 3246 | /// #![feature(int_roundings)] |
| 3247 | #[doc = concat!("let a: " , stringify!($SelfT)," = 8;" )] |
| 3248 | /// let b = 3; |
| 3249 | /// |
| 3250 | /// assert_eq!(a.div_floor(b), 2); |
| 3251 | /// assert_eq!(a.div_floor(-b), -3); |
| 3252 | /// assert_eq!((-a).div_floor(b), -3); |
| 3253 | /// assert_eq!((-a).div_floor(-b), 2); |
| 3254 | /// ``` |
| 3255 | #[unstable(feature = "int_roundings" , issue = "88581" )] |
| 3256 | #[must_use = "this returns the result of the operation, \ |
| 3257 | without modifying the original" ] |
| 3258 | #[inline] |
| 3259 | #[track_caller] |
| 3260 | pub const fn div_floor(self, rhs: Self) -> Self { |
| 3261 | let d = self / rhs; |
| 3262 | let r = self % rhs; |
| 3263 | |
| 3264 | // If the remainder is non-zero, we need to subtract one if the |
| 3265 | // signs of self and rhs differ, as this means we rounded upwards |
| 3266 | // instead of downwards. We do this branchlessly by creating a mask |
| 3267 | // which is all-ones iff the signs differ, and 0 otherwise. Then by |
| 3268 | // adding this mask (which corresponds to the signed value -1), we |
| 3269 | // get our correction. |
| 3270 | let correction = (self ^ rhs) >> (Self::BITS - 1); |
| 3271 | if r != 0 { |
| 3272 | d + correction |
| 3273 | } else { |
| 3274 | d |
| 3275 | } |
| 3276 | } |
| 3277 | |
| 3278 | /// Calculates the quotient of `self` and `rhs`, rounding the result towards positive infinity. |
| 3279 | /// |
| 3280 | /// # Panics |
| 3281 | /// |
| 3282 | /// This function will panic if `rhs` is zero or if `self` is `Self::MIN` |
| 3283 | /// and `rhs` is -1. This behavior is not affected by the `overflow-checks` flag. |
| 3284 | /// |
| 3285 | /// # Examples |
| 3286 | /// |
| 3287 | /// ``` |
| 3288 | /// #![feature(int_roundings)] |
| 3289 | #[doc = concat!("let a: " , stringify!($SelfT)," = 8;" )] |
| 3290 | /// let b = 3; |
| 3291 | /// |
| 3292 | /// assert_eq!(a.div_ceil(b), 3); |
| 3293 | /// assert_eq!(a.div_ceil(-b), -2); |
| 3294 | /// assert_eq!((-a).div_ceil(b), -2); |
| 3295 | /// assert_eq!((-a).div_ceil(-b), 3); |
| 3296 | /// ``` |
| 3297 | #[unstable(feature = "int_roundings" , issue = "88581" )] |
| 3298 | #[must_use = "this returns the result of the operation, \ |
| 3299 | without modifying the original" ] |
| 3300 | #[inline] |
| 3301 | #[track_caller] |
| 3302 | pub const fn div_ceil(self, rhs: Self) -> Self { |
| 3303 | let d = self / rhs; |
| 3304 | let r = self % rhs; |
| 3305 | |
| 3306 | // When remainder is non-zero we have a.div_ceil(b) == 1 + a.div_floor(b), |
| 3307 | // so we can re-use the algorithm from div_floor, just adding 1. |
| 3308 | let correction = 1 + ((self ^ rhs) >> (Self::BITS - 1)); |
| 3309 | if r != 0 { |
| 3310 | d + correction |
| 3311 | } else { |
| 3312 | d |
| 3313 | } |
| 3314 | } |
| 3315 | |
| 3316 | /// If `rhs` is positive, calculates the smallest value greater than or |
| 3317 | /// equal to `self` that is a multiple of `rhs`. If `rhs` is negative, |
| 3318 | /// calculates the largest value less than or equal to `self` that is a |
| 3319 | /// multiple of `rhs`. |
| 3320 | /// |
| 3321 | /// # Panics |
| 3322 | /// |
| 3323 | /// This function will panic if `rhs` is zero. |
| 3324 | /// |
| 3325 | /// ## Overflow behavior |
| 3326 | /// |
| 3327 | /// On overflow, this function will panic if overflow checks are enabled (default in debug |
| 3328 | /// mode) and wrap if overflow checks are disabled (default in release mode). |
| 3329 | /// |
| 3330 | /// # Examples |
| 3331 | /// |
| 3332 | /// ``` |
| 3333 | /// #![feature(int_roundings)] |
| 3334 | #[doc = concat!("assert_eq!(16_" , stringify!($SelfT), ".next_multiple_of(8), 16);" )] |
| 3335 | #[doc = concat!("assert_eq!(23_" , stringify!($SelfT), ".next_multiple_of(8), 24);" )] |
| 3336 | #[doc = concat!("assert_eq!(16_" , stringify!($SelfT), ".next_multiple_of(-8), 16);" )] |
| 3337 | #[doc = concat!("assert_eq!(23_" , stringify!($SelfT), ".next_multiple_of(-8), 16);" )] |
| 3338 | #[doc = concat!("assert_eq!((-16_" , stringify!($SelfT), ").next_multiple_of(8), -16);" )] |
| 3339 | #[doc = concat!("assert_eq!((-23_" , stringify!($SelfT), ").next_multiple_of(8), -16);" )] |
| 3340 | #[doc = concat!("assert_eq!((-16_" , stringify!($SelfT), ").next_multiple_of(-8), -16);" )] |
| 3341 | #[doc = concat!("assert_eq!((-23_" , stringify!($SelfT), ").next_multiple_of(-8), -24);" )] |
| 3342 | /// ``` |
| 3343 | #[unstable(feature = "int_roundings" , issue = "88581" )] |
| 3344 | #[must_use = "this returns the result of the operation, \ |
| 3345 | without modifying the original" ] |
| 3346 | #[inline] |
| 3347 | #[rustc_inherit_overflow_checks] |
| 3348 | pub const fn next_multiple_of(self, rhs: Self) -> Self { |
| 3349 | // This would otherwise fail when calculating `r` when self == T::MIN. |
| 3350 | if rhs == -1 { |
| 3351 | return self; |
| 3352 | } |
| 3353 | |
| 3354 | let r = self % rhs; |
| 3355 | let m = if (r > 0 && rhs < 0) || (r < 0 && rhs > 0) { |
| 3356 | r + rhs |
| 3357 | } else { |
| 3358 | r |
| 3359 | }; |
| 3360 | |
| 3361 | if m == 0 { |
| 3362 | self |
| 3363 | } else { |
| 3364 | self + (rhs - m) |
| 3365 | } |
| 3366 | } |
| 3367 | |
| 3368 | /// If `rhs` is positive, calculates the smallest value greater than or |
| 3369 | /// equal to `self` that is a multiple of `rhs`. If `rhs` is negative, |
| 3370 | /// calculates the largest value less than or equal to `self` that is a |
| 3371 | /// multiple of `rhs`. Returns `None` if `rhs` is zero or the operation |
| 3372 | /// would result in overflow. |
| 3373 | /// |
| 3374 | /// # Examples |
| 3375 | /// |
| 3376 | /// ``` |
| 3377 | /// #![feature(int_roundings)] |
| 3378 | #[doc = concat!("assert_eq!(16_" , stringify!($SelfT), ".checked_next_multiple_of(8), Some(16));" )] |
| 3379 | #[doc = concat!("assert_eq!(23_" , stringify!($SelfT), ".checked_next_multiple_of(8), Some(24));" )] |
| 3380 | #[doc = concat!("assert_eq!(16_" , stringify!($SelfT), ".checked_next_multiple_of(-8), Some(16));" )] |
| 3381 | #[doc = concat!("assert_eq!(23_" , stringify!($SelfT), ".checked_next_multiple_of(-8), Some(16));" )] |
| 3382 | #[doc = concat!("assert_eq!((-16_" , stringify!($SelfT), ").checked_next_multiple_of(8), Some(-16));" )] |
| 3383 | #[doc = concat!("assert_eq!((-23_" , stringify!($SelfT), ").checked_next_multiple_of(8), Some(-16));" )] |
| 3384 | #[doc = concat!("assert_eq!((-16_" , stringify!($SelfT), ").checked_next_multiple_of(-8), Some(-16));" )] |
| 3385 | #[doc = concat!("assert_eq!((-23_" , stringify!($SelfT), ").checked_next_multiple_of(-8), Some(-24));" )] |
| 3386 | #[doc = concat!("assert_eq!(1_" , stringify!($SelfT), ".checked_next_multiple_of(0), None);" )] |
| 3387 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MAX.checked_next_multiple_of(2), None);" )] |
| 3388 | /// ``` |
| 3389 | #[unstable(feature = "int_roundings" , issue = "88581" )] |
| 3390 | #[must_use = "this returns the result of the operation, \ |
| 3391 | without modifying the original" ] |
| 3392 | #[inline] |
| 3393 | pub const fn checked_next_multiple_of(self, rhs: Self) -> Option<Self> { |
| 3394 | // This would otherwise fail when calculating `r` when self == T::MIN. |
| 3395 | if rhs == -1 { |
| 3396 | return Some(self); |
| 3397 | } |
| 3398 | |
| 3399 | let r = try_opt!(self.checked_rem(rhs)); |
| 3400 | let m = if (r > 0 && rhs < 0) || (r < 0 && rhs > 0) { |
| 3401 | // r + rhs cannot overflow because they have opposite signs |
| 3402 | r + rhs |
| 3403 | } else { |
| 3404 | r |
| 3405 | }; |
| 3406 | |
| 3407 | if m == 0 { |
| 3408 | Some(self) |
| 3409 | } else { |
| 3410 | // rhs - m cannot overflow because m has the same sign as rhs |
| 3411 | self.checked_add(rhs - m) |
| 3412 | } |
| 3413 | } |
| 3414 | |
| 3415 | /// Returns the logarithm of the number with respect to an arbitrary base, |
| 3416 | /// rounded down. |
| 3417 | /// |
| 3418 | /// This method might not be optimized owing to implementation details; |
| 3419 | /// `ilog2` can produce results more efficiently for base 2, and `ilog10` |
| 3420 | /// can produce results more efficiently for base 10. |
| 3421 | /// |
| 3422 | /// # Panics |
| 3423 | /// |
| 3424 | /// This function will panic if `self` is less than or equal to zero, |
| 3425 | /// or if `base` is less than 2. |
| 3426 | /// |
| 3427 | /// # Examples |
| 3428 | /// |
| 3429 | /// ``` |
| 3430 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".ilog(5), 1);" )] |
| 3431 | /// ``` |
| 3432 | #[stable(feature = "int_log" , since = "1.67.0" )] |
| 3433 | #[rustc_const_stable(feature = "int_log" , since = "1.67.0" )] |
| 3434 | #[must_use = "this returns the result of the operation, \ |
| 3435 | without modifying the original" ] |
| 3436 | #[inline] |
| 3437 | #[track_caller] |
| 3438 | pub const fn ilog(self, base: Self) -> u32 { |
| 3439 | assert!(base >= 2, "base of integer logarithm must be at least 2" ); |
| 3440 | if let Some(log) = self.checked_ilog(base) { |
| 3441 | log |
| 3442 | } else { |
| 3443 | int_log10::panic_for_nonpositive_argument() |
| 3444 | } |
| 3445 | } |
| 3446 | |
| 3447 | /// Returns the base 2 logarithm of the number, rounded down. |
| 3448 | /// |
| 3449 | /// # Panics |
| 3450 | /// |
| 3451 | /// This function will panic if `self` is less than or equal to zero. |
| 3452 | /// |
| 3453 | /// # Examples |
| 3454 | /// |
| 3455 | /// ``` |
| 3456 | #[doc = concat!("assert_eq!(2" , stringify!($SelfT), ".ilog2(), 1);" )] |
| 3457 | /// ``` |
| 3458 | #[stable(feature = "int_log" , since = "1.67.0" )] |
| 3459 | #[rustc_const_stable(feature = "int_log" , since = "1.67.0" )] |
| 3460 | #[must_use = "this returns the result of the operation, \ |
| 3461 | without modifying the original" ] |
| 3462 | #[inline] |
| 3463 | #[track_caller] |
| 3464 | pub const fn ilog2(self) -> u32 { |
| 3465 | if let Some(log) = self.checked_ilog2() { |
| 3466 | log |
| 3467 | } else { |
| 3468 | int_log10::panic_for_nonpositive_argument() |
| 3469 | } |
| 3470 | } |
| 3471 | |
| 3472 | /// Returns the base 10 logarithm of the number, rounded down. |
| 3473 | /// |
| 3474 | /// # Panics |
| 3475 | /// |
| 3476 | /// This function will panic if `self` is less than or equal to zero. |
| 3477 | /// |
| 3478 | /// # Example |
| 3479 | /// |
| 3480 | /// ``` |
| 3481 | #[doc = concat!("assert_eq!(10" , stringify!($SelfT), ".ilog10(), 1);" )] |
| 3482 | /// ``` |
| 3483 | #[stable(feature = "int_log" , since = "1.67.0" )] |
| 3484 | #[rustc_const_stable(feature = "int_log" , since = "1.67.0" )] |
| 3485 | #[must_use = "this returns the result of the operation, \ |
| 3486 | without modifying the original" ] |
| 3487 | #[inline] |
| 3488 | #[track_caller] |
| 3489 | pub const fn ilog10(self) -> u32 { |
| 3490 | if let Some(log) = self.checked_ilog10() { |
| 3491 | log |
| 3492 | } else { |
| 3493 | int_log10::panic_for_nonpositive_argument() |
| 3494 | } |
| 3495 | } |
| 3496 | |
| 3497 | /// Returns the logarithm of the number with respect to an arbitrary base, |
| 3498 | /// rounded down. |
| 3499 | /// |
| 3500 | /// Returns `None` if the number is negative or zero, or if the base is not at least 2. |
| 3501 | /// |
| 3502 | /// This method might not be optimized owing to implementation details; |
| 3503 | /// `checked_ilog2` can produce results more efficiently for base 2, and |
| 3504 | /// `checked_ilog10` can produce results more efficiently for base 10. |
| 3505 | /// |
| 3506 | /// # Examples |
| 3507 | /// |
| 3508 | /// ``` |
| 3509 | #[doc = concat!("assert_eq!(5" , stringify!($SelfT), ".checked_ilog(5), Some(1));" )] |
| 3510 | /// ``` |
| 3511 | #[stable(feature = "int_log" , since = "1.67.0" )] |
| 3512 | #[rustc_const_stable(feature = "int_log" , since = "1.67.0" )] |
| 3513 | #[must_use = "this returns the result of the operation, \ |
| 3514 | without modifying the original" ] |
| 3515 | #[inline] |
| 3516 | pub const fn checked_ilog(self, base: Self) -> Option<u32> { |
| 3517 | if self <= 0 || base <= 1 { |
| 3518 | None |
| 3519 | } else { |
| 3520 | // Delegate to the unsigned implementation. |
| 3521 | // The condition makes sure that both casts are exact. |
| 3522 | (self as $UnsignedT).checked_ilog(base as $UnsignedT) |
| 3523 | } |
| 3524 | } |
| 3525 | |
| 3526 | /// Returns the base 2 logarithm of the number, rounded down. |
| 3527 | /// |
| 3528 | /// Returns `None` if the number is negative or zero. |
| 3529 | /// |
| 3530 | /// # Examples |
| 3531 | /// |
| 3532 | /// ``` |
| 3533 | #[doc = concat!("assert_eq!(2" , stringify!($SelfT), ".checked_ilog2(), Some(1));" )] |
| 3534 | /// ``` |
| 3535 | #[stable(feature = "int_log" , since = "1.67.0" )] |
| 3536 | #[rustc_const_stable(feature = "int_log" , since = "1.67.0" )] |
| 3537 | #[must_use = "this returns the result of the operation, \ |
| 3538 | without modifying the original" ] |
| 3539 | #[inline] |
| 3540 | pub const fn checked_ilog2(self) -> Option<u32> { |
| 3541 | if self <= 0 { |
| 3542 | None |
| 3543 | } else { |
| 3544 | // SAFETY: We just checked that this number is positive |
| 3545 | let log = (Self::BITS - 1) - unsafe { intrinsics::ctlz_nonzero(self) as u32 }; |
| 3546 | Some(log) |
| 3547 | } |
| 3548 | } |
| 3549 | |
| 3550 | /// Returns the base 10 logarithm of the number, rounded down. |
| 3551 | /// |
| 3552 | /// Returns `None` if the number is negative or zero. |
| 3553 | /// |
| 3554 | /// # Example |
| 3555 | /// |
| 3556 | /// ``` |
| 3557 | #[doc = concat!("assert_eq!(10" , stringify!($SelfT), ".checked_ilog10(), Some(1));" )] |
| 3558 | /// ``` |
| 3559 | #[stable(feature = "int_log" , since = "1.67.0" )] |
| 3560 | #[rustc_const_stable(feature = "int_log" , since = "1.67.0" )] |
| 3561 | #[must_use = "this returns the result of the operation, \ |
| 3562 | without modifying the original" ] |
| 3563 | #[inline] |
| 3564 | pub const fn checked_ilog10(self) -> Option<u32> { |
| 3565 | int_log10::$ActualT(self as $ActualT) |
| 3566 | } |
| 3567 | |
| 3568 | /// Computes the absolute value of `self`. |
| 3569 | /// |
| 3570 | /// # Overflow behavior |
| 3571 | /// |
| 3572 | /// The absolute value of |
| 3573 | #[doc = concat!("`" , stringify!($SelfT), "::MIN`" )] |
| 3574 | /// cannot be represented as an |
| 3575 | #[doc = concat!("`" , stringify!($SelfT), "`," )] |
| 3576 | /// and attempting to calculate it will cause an overflow. This means |
| 3577 | /// that code in debug mode will trigger a panic on this case and |
| 3578 | /// optimized code will return |
| 3579 | #[doc = concat!("`" , stringify!($SelfT), "::MIN`" )] |
| 3580 | /// without a panic. If you do not want this behavior, consider |
| 3581 | /// using [`unsigned_abs`](Self::unsigned_abs) instead. |
| 3582 | /// |
| 3583 | /// # Examples |
| 3584 | /// |
| 3585 | /// ``` |
| 3586 | #[doc = concat!("assert_eq!(10" , stringify!($SelfT), ".abs(), 10);" )] |
| 3587 | #[doc = concat!("assert_eq!((-10" , stringify!($SelfT), ").abs(), 10);" )] |
| 3588 | /// ``` |
| 3589 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 3590 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 3591 | #[allow(unused_attributes)] |
| 3592 | #[must_use = "this returns the result of the operation, \ |
| 3593 | without modifying the original" ] |
| 3594 | #[inline] |
| 3595 | #[rustc_inherit_overflow_checks] |
| 3596 | pub const fn abs(self) -> Self { |
| 3597 | // Note that the #[rustc_inherit_overflow_checks] and #[inline] |
| 3598 | // above mean that the overflow semantics of the subtraction |
| 3599 | // depend on the crate we're being called from. |
| 3600 | if self.is_negative() { |
| 3601 | -self |
| 3602 | } else { |
| 3603 | self |
| 3604 | } |
| 3605 | } |
| 3606 | |
| 3607 | /// Computes the absolute difference between `self` and `other`. |
| 3608 | /// |
| 3609 | /// This function always returns the correct answer without overflow or |
| 3610 | /// panics by returning an unsigned integer. |
| 3611 | /// |
| 3612 | /// # Examples |
| 3613 | /// |
| 3614 | /// ``` |
| 3615 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".abs_diff(80), 20" , stringify!($UnsignedT), ");" )] |
| 3616 | #[doc = concat!("assert_eq!(100" , stringify!($SelfT), ".abs_diff(110), 10" , stringify!($UnsignedT), ");" )] |
| 3617 | #[doc = concat!("assert_eq!((-100" , stringify!($SelfT), ").abs_diff(80), 180" , stringify!($UnsignedT), ");" )] |
| 3618 | #[doc = concat!("assert_eq!((-100" , stringify!($SelfT), ").abs_diff(-120), 20" , stringify!($UnsignedT), ");" )] |
| 3619 | #[doc = concat!("assert_eq!(" , stringify!($SelfT), "::MIN.abs_diff(" , stringify!($SelfT), "::MAX), " , stringify!($UnsignedT), "::MAX);" )] |
| 3620 | /// ``` |
| 3621 | #[stable(feature = "int_abs_diff" , since = "1.60.0" )] |
| 3622 | #[rustc_const_stable(feature = "int_abs_diff" , since = "1.60.0" )] |
| 3623 | #[must_use = "this returns the result of the operation, \ |
| 3624 | without modifying the original" ] |
| 3625 | #[inline] |
| 3626 | pub const fn abs_diff(self, other: Self) -> $UnsignedT { |
| 3627 | if self < other { |
| 3628 | // Converting a non-negative x from signed to unsigned by using |
| 3629 | // `x as U` is left unchanged, but a negative x is converted |
| 3630 | // to value x + 2^N. Thus if `s` and `o` are binary variables |
| 3631 | // respectively indicating whether `self` and `other` are |
| 3632 | // negative, we are computing the mathematical value: |
| 3633 | // |
| 3634 | // (other + o*2^N) - (self + s*2^N) mod 2^N |
| 3635 | // other - self + (o-s)*2^N mod 2^N |
| 3636 | // other - self mod 2^N |
| 3637 | // |
| 3638 | // Finally, taking the mod 2^N of the mathematical value of |
| 3639 | // `other - self` does not change it as it already is |
| 3640 | // in the range [0, 2^N). |
| 3641 | (other as $UnsignedT).wrapping_sub(self as $UnsignedT) |
| 3642 | } else { |
| 3643 | (self as $UnsignedT).wrapping_sub(other as $UnsignedT) |
| 3644 | } |
| 3645 | } |
| 3646 | |
| 3647 | /// Returns a number representing sign of `self`. |
| 3648 | /// |
| 3649 | /// - `0` if the number is zero |
| 3650 | /// - `1` if the number is positive |
| 3651 | /// - `-1` if the number is negative |
| 3652 | /// |
| 3653 | /// # Examples |
| 3654 | /// |
| 3655 | /// ``` |
| 3656 | #[doc = concat!("assert_eq!(10" , stringify!($SelfT), ".signum(), 1);" )] |
| 3657 | #[doc = concat!("assert_eq!(0" , stringify!($SelfT), ".signum(), 0);" )] |
| 3658 | #[doc = concat!("assert_eq!((-10" , stringify!($SelfT), ").signum(), -1);" )] |
| 3659 | /// ``` |
| 3660 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 3661 | #[rustc_const_stable(feature = "const_int_sign" , since = "1.47.0" )] |
| 3662 | #[must_use = "this returns the result of the operation, \ |
| 3663 | without modifying the original" ] |
| 3664 | #[inline(always)] |
| 3665 | pub const fn signum(self) -> Self { |
| 3666 | // Picking the right way to phrase this is complicated |
| 3667 | // (<https://graphics.stanford.edu/~seander/bithacks.html#CopyIntegerSign>) |
| 3668 | // so delegate it to `Ord` which is already producing -1/0/+1 |
| 3669 | // exactly like we need and can be the place to deal with the complexity. |
| 3670 | |
| 3671 | crate::intrinsics::three_way_compare(self, 0) as Self |
| 3672 | } |
| 3673 | |
| 3674 | /// Returns `true` if `self` is positive and `false` if the number is zero or |
| 3675 | /// negative. |
| 3676 | /// |
| 3677 | /// # Examples |
| 3678 | /// |
| 3679 | /// ``` |
| 3680 | #[doc = concat!("assert!(10" , stringify!($SelfT), ".is_positive());" )] |
| 3681 | #[doc = concat!("assert!(!(-10" , stringify!($SelfT), ").is_positive());" )] |
| 3682 | /// ``` |
| 3683 | #[must_use] |
| 3684 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 3685 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 3686 | #[inline(always)] |
| 3687 | pub const fn is_positive(self) -> bool { self > 0 } |
| 3688 | |
| 3689 | /// Returns `true` if `self` is negative and `false` if the number is zero or |
| 3690 | /// positive. |
| 3691 | /// |
| 3692 | /// # Examples |
| 3693 | /// |
| 3694 | /// ``` |
| 3695 | #[doc = concat!("assert!((-10" , stringify!($SelfT), ").is_negative());" )] |
| 3696 | #[doc = concat!("assert!(!10" , stringify!($SelfT), ".is_negative());" )] |
| 3697 | /// ``` |
| 3698 | #[must_use] |
| 3699 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 3700 | #[rustc_const_stable(feature = "const_int_methods" , since = "1.32.0" )] |
| 3701 | #[inline(always)] |
| 3702 | pub const fn is_negative(self) -> bool { self < 0 } |
| 3703 | |
| 3704 | /// Returns the memory representation of this integer as a byte array in |
| 3705 | /// big-endian (network) byte order. |
| 3706 | /// |
| 3707 | #[doc = $to_xe_bytes_doc] |
| 3708 | /// |
| 3709 | /// # Examples |
| 3710 | /// |
| 3711 | /// ``` |
| 3712 | #[doc = concat!("let bytes = " , $swap_op, stringify!($SelfT), ".to_be_bytes();" )] |
| 3713 | #[doc = concat!("assert_eq!(bytes, " , $be_bytes, ");" )] |
| 3714 | /// ``` |
| 3715 | #[stable(feature = "int_to_from_bytes" , since = "1.32.0" )] |
| 3716 | #[rustc_const_stable(feature = "const_int_conversion" , since = "1.44.0" )] |
| 3717 | #[must_use = "this returns the result of the operation, \ |
| 3718 | without modifying the original" ] |
| 3719 | #[inline] |
| 3720 | pub const fn to_be_bytes(self) -> [u8; size_of::<Self>()] { |
| 3721 | self.to_be().to_ne_bytes() |
| 3722 | } |
| 3723 | |
| 3724 | /// Returns the memory representation of this integer as a byte array in |
| 3725 | /// little-endian byte order. |
| 3726 | /// |
| 3727 | #[doc = $to_xe_bytes_doc] |
| 3728 | /// |
| 3729 | /// # Examples |
| 3730 | /// |
| 3731 | /// ``` |
| 3732 | #[doc = concat!("let bytes = " , $swap_op, stringify!($SelfT), ".to_le_bytes();" )] |
| 3733 | #[doc = concat!("assert_eq!(bytes, " , $le_bytes, ");" )] |
| 3734 | /// ``` |
| 3735 | #[stable(feature = "int_to_from_bytes" , since = "1.32.0" )] |
| 3736 | #[rustc_const_stable(feature = "const_int_conversion" , since = "1.44.0" )] |
| 3737 | #[must_use = "this returns the result of the operation, \ |
| 3738 | without modifying the original" ] |
| 3739 | #[inline] |
| 3740 | pub const fn to_le_bytes(self) -> [u8; size_of::<Self>()] { |
| 3741 | self.to_le().to_ne_bytes() |
| 3742 | } |
| 3743 | |
| 3744 | /// Returns the memory representation of this integer as a byte array in |
| 3745 | /// native byte order. |
| 3746 | /// |
| 3747 | /// As the target platform's native endianness is used, portable code |
| 3748 | /// should use [`to_be_bytes`] or [`to_le_bytes`], as appropriate, |
| 3749 | /// instead. |
| 3750 | /// |
| 3751 | #[doc = $to_xe_bytes_doc] |
| 3752 | /// |
| 3753 | /// [`to_be_bytes`]: Self::to_be_bytes |
| 3754 | /// [`to_le_bytes`]: Self::to_le_bytes |
| 3755 | /// |
| 3756 | /// # Examples |
| 3757 | /// |
| 3758 | /// ``` |
| 3759 | #[doc = concat!("let bytes = " , $swap_op, stringify!($SelfT), ".to_ne_bytes();" )] |
| 3760 | /// assert_eq!( |
| 3761 | /// bytes, |
| 3762 | /// if cfg!(target_endian = "big") { |
| 3763 | #[doc = concat!(" " , $be_bytes)] |
| 3764 | /// } else { |
| 3765 | #[doc = concat!(" " , $le_bytes)] |
| 3766 | /// } |
| 3767 | /// ); |
| 3768 | /// ``` |
| 3769 | #[stable(feature = "int_to_from_bytes" , since = "1.32.0" )] |
| 3770 | #[rustc_const_stable(feature = "const_int_conversion" , since = "1.44.0" )] |
| 3771 | #[allow(unnecessary_transmutes)] |
| 3772 | // SAFETY: const sound because integers are plain old datatypes so we can always |
| 3773 | // transmute them to arrays of bytes |
| 3774 | #[must_use = "this returns the result of the operation, \ |
| 3775 | without modifying the original" ] |
| 3776 | #[inline] |
| 3777 | pub const fn to_ne_bytes(self) -> [u8; size_of::<Self>()] { |
| 3778 | // SAFETY: integers are plain old datatypes so we can always transmute them to |
| 3779 | // arrays of bytes |
| 3780 | unsafe { mem::transmute(self) } |
| 3781 | } |
| 3782 | |
| 3783 | /// Creates an integer value from its representation as a byte array in |
| 3784 | /// big endian. |
| 3785 | /// |
| 3786 | #[doc = $from_xe_bytes_doc] |
| 3787 | /// |
| 3788 | /// # Examples |
| 3789 | /// |
| 3790 | /// ``` |
| 3791 | #[doc = concat!("let value = " , stringify!($SelfT), "::from_be_bytes(" , $be_bytes, ");" )] |
| 3792 | #[doc = concat!("assert_eq!(value, " , $swap_op, ");" )] |
| 3793 | /// ``` |
| 3794 | /// |
| 3795 | /// When starting from a slice rather than an array, fallible conversion APIs can be used: |
| 3796 | /// |
| 3797 | /// ``` |
| 3798 | #[doc = concat!("fn read_be_" , stringify!($SelfT), "(input: &mut &[u8]) -> " , stringify!($SelfT), " {" )] |
| 3799 | #[doc = concat!(" let (int_bytes, rest) = input.split_at(size_of::<" , stringify!($SelfT), ">());" )] |
| 3800 | /// *input = rest; |
| 3801 | #[doc = concat!(" " , stringify!($SelfT), "::from_be_bytes(int_bytes.try_into().unwrap())" )] |
| 3802 | /// } |
| 3803 | /// ``` |
| 3804 | #[stable(feature = "int_to_from_bytes" , since = "1.32.0" )] |
| 3805 | #[rustc_const_stable(feature = "const_int_conversion" , since = "1.44.0" )] |
| 3806 | #[must_use] |
| 3807 | #[inline] |
| 3808 | pub const fn from_be_bytes(bytes: [u8; size_of::<Self>()]) -> Self { |
| 3809 | Self::from_be(Self::from_ne_bytes(bytes)) |
| 3810 | } |
| 3811 | |
| 3812 | /// Creates an integer value from its representation as a byte array in |
| 3813 | /// little endian. |
| 3814 | /// |
| 3815 | #[doc = $from_xe_bytes_doc] |
| 3816 | /// |
| 3817 | /// # Examples |
| 3818 | /// |
| 3819 | /// ``` |
| 3820 | #[doc = concat!("let value = " , stringify!($SelfT), "::from_le_bytes(" , $le_bytes, ");" )] |
| 3821 | #[doc = concat!("assert_eq!(value, " , $swap_op, ");" )] |
| 3822 | /// ``` |
| 3823 | /// |
| 3824 | /// When starting from a slice rather than an array, fallible conversion APIs can be used: |
| 3825 | /// |
| 3826 | /// ``` |
| 3827 | #[doc = concat!("fn read_le_" , stringify!($SelfT), "(input: &mut &[u8]) -> " , stringify!($SelfT), " {" )] |
| 3828 | #[doc = concat!(" let (int_bytes, rest) = input.split_at(size_of::<" , stringify!($SelfT), ">());" )] |
| 3829 | /// *input = rest; |
| 3830 | #[doc = concat!(" " , stringify!($SelfT), "::from_le_bytes(int_bytes.try_into().unwrap())" )] |
| 3831 | /// } |
| 3832 | /// ``` |
| 3833 | #[stable(feature = "int_to_from_bytes" , since = "1.32.0" )] |
| 3834 | #[rustc_const_stable(feature = "const_int_conversion" , since = "1.44.0" )] |
| 3835 | #[must_use] |
| 3836 | #[inline] |
| 3837 | pub const fn from_le_bytes(bytes: [u8; size_of::<Self>()]) -> Self { |
| 3838 | Self::from_le(Self::from_ne_bytes(bytes)) |
| 3839 | } |
| 3840 | |
| 3841 | /// Creates an integer value from its memory representation as a byte |
| 3842 | /// array in native endianness. |
| 3843 | /// |
| 3844 | /// As the target platform's native endianness is used, portable code |
| 3845 | /// likely wants to use [`from_be_bytes`] or [`from_le_bytes`], as |
| 3846 | /// appropriate instead. |
| 3847 | /// |
| 3848 | /// [`from_be_bytes`]: Self::from_be_bytes |
| 3849 | /// [`from_le_bytes`]: Self::from_le_bytes |
| 3850 | /// |
| 3851 | #[doc = $from_xe_bytes_doc] |
| 3852 | /// |
| 3853 | /// # Examples |
| 3854 | /// |
| 3855 | /// ``` |
| 3856 | #[doc = concat!("let value = " , stringify!($SelfT), "::from_ne_bytes(if cfg!(target_endian = \"big \") {" )] |
| 3857 | #[doc = concat!(" " , $be_bytes)] |
| 3858 | /// } else { |
| 3859 | #[doc = concat!(" " , $le_bytes)] |
| 3860 | /// }); |
| 3861 | #[doc = concat!("assert_eq!(value, " , $swap_op, ");" )] |
| 3862 | /// ``` |
| 3863 | /// |
| 3864 | /// When starting from a slice rather than an array, fallible conversion APIs can be used: |
| 3865 | /// |
| 3866 | /// ``` |
| 3867 | #[doc = concat!("fn read_ne_" , stringify!($SelfT), "(input: &mut &[u8]) -> " , stringify!($SelfT), " {" )] |
| 3868 | #[doc = concat!(" let (int_bytes, rest) = input.split_at(size_of::<" , stringify!($SelfT), ">());" )] |
| 3869 | /// *input = rest; |
| 3870 | #[doc = concat!(" " , stringify!($SelfT), "::from_ne_bytes(int_bytes.try_into().unwrap())" )] |
| 3871 | /// } |
| 3872 | /// ``` |
| 3873 | #[stable(feature = "int_to_from_bytes" , since = "1.32.0" )] |
| 3874 | #[rustc_const_stable(feature = "const_int_conversion" , since = "1.44.0" )] |
| 3875 | #[allow(unnecessary_transmutes)] |
| 3876 | #[must_use] |
| 3877 | // SAFETY: const sound because integers are plain old datatypes so we can always |
| 3878 | // transmute to them |
| 3879 | #[inline] |
| 3880 | pub const fn from_ne_bytes(bytes: [u8; size_of::<Self>()]) -> Self { |
| 3881 | // SAFETY: integers are plain old datatypes so we can always transmute to them |
| 3882 | unsafe { mem::transmute(bytes) } |
| 3883 | } |
| 3884 | |
| 3885 | /// New code should prefer to use |
| 3886 | #[doc = concat!("[`" , stringify!($SelfT), "::MIN" , "`] instead." )] |
| 3887 | /// |
| 3888 | /// Returns the smallest value that can be represented by this integer type. |
| 3889 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 3890 | #[inline(always)] |
| 3891 | #[rustc_promotable] |
| 3892 | #[rustc_const_stable(feature = "const_min_value" , since = "1.32.0" )] |
| 3893 | #[deprecated(since = "TBD" , note = "replaced by the `MIN` associated constant on this type" )] |
| 3894 | #[rustc_diagnostic_item = concat!(stringify!($SelfT), "_legacy_fn_min_value" )] |
| 3895 | pub const fn min_value() -> Self { |
| 3896 | Self::MIN |
| 3897 | } |
| 3898 | |
| 3899 | /// New code should prefer to use |
| 3900 | #[doc = concat!("[`" , stringify!($SelfT), "::MAX" , "`] instead." )] |
| 3901 | /// |
| 3902 | /// Returns the largest value that can be represented by this integer type. |
| 3903 | #[stable(feature = "rust1" , since = "1.0.0" )] |
| 3904 | #[inline(always)] |
| 3905 | #[rustc_promotable] |
| 3906 | #[rustc_const_stable(feature = "const_max_value" , since = "1.32.0" )] |
| 3907 | #[deprecated(since = "TBD" , note = "replaced by the `MAX` associated constant on this type" )] |
| 3908 | #[rustc_diagnostic_item = concat!(stringify!($SelfT), "_legacy_fn_max_value" )] |
| 3909 | pub const fn max_value() -> Self { |
| 3910 | Self::MAX |
| 3911 | } |
| 3912 | |
| 3913 | /// Clamps this number to a symmetric range centred around zero. |
| 3914 | /// |
| 3915 | /// The method clamps the number's magnitude (absolute value) to be at most `limit`. |
| 3916 | /// |
| 3917 | /// This is functionally equivalent to `self.clamp(-limit, limit)`, but is more |
| 3918 | /// explicit about the intent. |
| 3919 | /// |
| 3920 | /// # Examples |
| 3921 | /// |
| 3922 | /// ``` |
| 3923 | /// #![feature(clamp_magnitude)] |
| 3924 | #[doc = concat!("assert_eq!(120" , stringify!($SelfT), ".clamp_magnitude(100), 100);" )] |
| 3925 | #[doc = concat!("assert_eq!(-120" , stringify!($SelfT), ".clamp_magnitude(100), -100);" )] |
| 3926 | #[doc = concat!("assert_eq!(80" , stringify!($SelfT), ".clamp_magnitude(100), 80);" )] |
| 3927 | #[doc = concat!("assert_eq!(-80" , stringify!($SelfT), ".clamp_magnitude(100), -80);" )] |
| 3928 | /// ``` |
| 3929 | #[must_use = "this returns the clamped value and does not modify the original" ] |
| 3930 | #[unstable(feature = "clamp_magnitude" , issue = "148519" )] |
| 3931 | #[inline] |
| 3932 | pub fn clamp_magnitude(self, limit: $UnsignedT) -> Self { |
| 3933 | if let Ok(limit) = core::convert::TryInto::<$SelfT>::try_into(limit) { |
| 3934 | self.clamp(-limit, limit) |
| 3935 | } else { |
| 3936 | self |
| 3937 | } |
| 3938 | } |
| 3939 | } |
| 3940 | } |
| 3941 | |