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| author | Niko Matsakis <niko@alum.mit.edu> | 2018-07-25 13:43:35 +0300 |
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| committer | Niko Matsakis <niko@alum.mit.edu> | 2018-09-07 11:34:41 -0400 |
| commit | c46f185f670ff051f56f48d7f19da4b116a6128a (patch) | |
| tree | e1dfba836789be8b3b71e73b5d16c7a60e38b0b6 /src/librustc_data_structures | |
| parent | 1242639b88b0dee9ebb0f103efe017826c5b334e (diff) | |
| download | rust-c46f185f670ff051f56f48d7f19da4b116a6128a.tar.gz rust-c46f185f670ff051f56f48d7f19da4b116a6128a.zip | |
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Diffstat (limited to 'src/librustc_data_structures')
| -rw-r--r-- | src/librustc_data_structures/indexed_vec.rs | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/src/librustc_data_structures/indexed_vec.rs b/src/librustc_data_structures/indexed_vec.rs index f8992c991cc..09015957f99 100644 --- a/src/librustc_data_structures/indexed_vec.rs +++ b/src/librustc_data_structures/indexed_vec.rs @@ -48,6 +48,13 @@ impl Idx for u32 { fn index(self) -> usize { self as usize } } +/// Creates a struct type `S` that can be used as an index with +/// `IndexVec` and so on. This struct can be constructed via `S::new` +/// (given a `usize`) and converted to a usize with the `index()` +/// method (from the `Idx` trait). Internally, the index uses a u32, +/// so the index must not exceed `u32::MAX`. You can also customize +/// things like the `Debug` impl, what traits are derived, and so +/// forth. #[macro_export] macro_rules! newtype_index { // ---- public rules ---- |