1use alloc::vec::Vec;
2
3use crate::bstr::BStr;
4
5/// A wrapper for `Vec<u8>` that provides convenient string oriented trait
6/// impls.
7///
8/// A `BString` has ownership over its contents and corresponds to
9/// a growable or shrinkable buffer. Its borrowed counterpart is a
10/// [`BStr`](struct.BStr.html), called a byte string slice.
11///
12/// Using a `BString` is just like using a `Vec<u8>`, since `BString`
13/// implements `Deref` to `Vec<u8>`. So all methods available on `Vec<u8>`
14/// are also available on `BString`.
15///
16/// # Examples
17///
18/// You can create a new `BString` from a `Vec<u8>` via a `From` impl:
19///
20/// ```
21/// use bstr::BString;
22///
23/// let s = BString::from("Hello, world!");
24/// ```
25///
26/// # Deref
27///
28/// The `BString` type implements `Deref` and `DerefMut`, where the target
29/// types are `&Vec<u8>` and `&mut Vec<u8>`, respectively. `Deref` permits all of the
30/// methods defined on `Vec<u8>` to be implicitly callable on any `BString`.
31///
32/// For more information about how deref works, see the documentation for the
33/// [`std::ops::Deref`](https://doc.rust-lang.org/std/ops/trait.Deref.html)
34/// trait.
35///
36/// # Representation
37///
38/// A `BString` has the same representation as a `Vec<u8>` and a `String`.
39/// That is, it is made up of three word sized components: a pointer to a
40/// region of memory containing the bytes, a length and a capacity.
41#[derive(Clone)]
42pub struct BString {
43 bytes: Vec<u8>,
44}
45
46impl BString {
47 /// Constructs a new `BString` from the given [`Vec`].
48 ///
49 /// # Examples
50 ///
51 /// ```
52 /// use bstr::BString;
53 ///
54 /// let mut b = BString::new(Vec::with_capacity(10));
55 /// ```
56 ///
57 /// This function is `const`:
58 ///
59 /// ```
60 /// use bstr::BString;
61 ///
62 /// const B: BString = BString::new(vec![]);
63 /// ```
64 #[inline]
65 pub const fn new(bytes: Vec<u8>) -> BString {
66 BString { bytes }
67 }
68
69 #[inline]
70 pub(crate) fn as_bytes(&self) -> &[u8] {
71 &self.bytes
72 }
73
74 #[inline]
75 pub(crate) fn as_bytes_mut(&mut self) -> &mut [u8] {
76 &mut self.bytes
77 }
78
79 #[inline]
80 pub(crate) fn as_bstr(&self) -> &BStr {
81 BStr::new(&self.bytes)
82 }
83
84 #[inline]
85 pub(crate) fn as_mut_bstr(&mut self) -> &mut BStr {
86 BStr::new_mut(&mut self.bytes)
87 }
88
89 #[inline]
90 pub(crate) fn as_vec(&self) -> &Vec<u8> {
91 &self.bytes
92 }
93
94 #[inline]
95 pub(crate) fn as_vec_mut(&mut self) -> &mut Vec<u8> {
96 &mut self.bytes
97 }
98
99 #[inline]
100 pub(crate) fn into_vec(self) -> Vec<u8> {
101 self.bytes
102 }
103}
104