1 | use crate::ast::NestedMeta; |
2 | use crate::util::PathList; |
3 | use crate::{FromMeta, Result}; |
4 | |
5 | /// A rule about which attributes to forward to the generated struct. |
6 | #[derive (Debug, Clone, PartialEq, Eq)] |
7 | pub enum ForwardAttrs { |
8 | All, |
9 | Only(PathList), |
10 | } |
11 | |
12 | impl ForwardAttrs { |
13 | /// Returns `true` if this will not forward any attributes. |
14 | pub fn is_empty(&self) -> bool { |
15 | match *self { |
16 | ForwardAttrs::All => false, |
17 | ForwardAttrs::Only(ref list: &PathList) => list.is_empty(), |
18 | } |
19 | } |
20 | } |
21 | |
22 | impl FromMeta for ForwardAttrs { |
23 | fn from_word() -> Result<Self> { |
24 | Ok(ForwardAttrs::All) |
25 | } |
26 | |
27 | fn from_list(nested: &[NestedMeta]) -> Result<Self> { |
28 | Ok(ForwardAttrs::Only(PathList::from_list(items:nested)?)) |
29 | } |
30 | } |
31 | |