bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Auto merge of #84147 - cuviper:array-method-dispatch, r=nikomatsakis,m-ou-se

Browse source 
Cautiously add IntoIterator for arrays by value

Add the attribute described in #84133, `#[rustc_skip_array_during_method_dispatch]`, which effectively hides a trait from method dispatch when the receiver type is an array.

Then cherry-pick `IntoIterator for [T; N]` from #65819 and gate it with that attribute. Arrays can now be used as `IntoIterator` normally, but `array.into_iter()` has edition-dependent behavior, returning `slice::Iter` for 2015 and 2018 editions, or `array::IntoIter` for 2021 and later.

r? `@nikomatsakis`
cc `@LukasKalbertodt` `@rust-lang/libs`
This commit is contained in:
bors 2021-04-25 07:26:49 +00:00
commit 13a2615883
18 changed files with 237 additions and 171 deletions
Download patch file Download diff file Expand all files Collapse all files

7
compiler/rustc_middle/src/ty/trait_def.rs
View file

@ -35,6 +35,11 @@ pub struct TraitDef {
/// and thus `impl`s of it are allowed to overlap.
pub is_marker: bool,
/// If `true`, then this trait has the `#[rustc_skip_array_during_method_dispatch]`
/// attribute, indicating that editions before 2021 should not consider this trait
/// during method dispatch if the receiver is an array.
pub skip_array_during_method_dispatch: bool,
/// Used to determine whether the standard library is allowed to specialize
/// on this trait.
pub specialization_kind: TraitSpecializationKind,
@ -82,6 +87,7 @@ impl<'tcx> TraitDef {
paren_sugar: bool,
has_auto_impl: bool,
is_marker: bool,
skip_array_during_method_dispatch: bool,
specialization_kind: TraitSpecializationKind,
def_path_hash: DefPathHash,
) -> TraitDef {
@ -91,6 +97,7 @@ impl<'tcx> TraitDef {
paren_sugar,
has_auto_impl,
is_marker,
skip_array_during_method_dispatch,
specialization_kind,
def_path_hash,
}