From eabd306265911c30641dbf8b263e0191a7e07f9a Mon Sep 17 00:00:00 2001 From: Maybe Waffle Date: Wed, 19 Jul 2023 09:44:40 +0000 Subject: [PATCH] Document `PredicateSet::insert` I always forget what the `bool` means :/ --- compiler/rustc_infer/src/traits/util.rs | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/compiler/rustc_infer/src/traits/util.rs b/compiler/rustc_infer/src/traits/util.rs index 074ff7ec97f..87ba6b3ec50 100644 --- a/compiler/rustc_infer/src/traits/util.rs +++ b/compiler/rustc_infer/src/traits/util.rs @@ -25,6 +25,13 @@ pub fn new(tcx: TyCtxt<'tcx>) -> Self { Self { tcx, set: Default::default() } } + /// Adds a predicate to the set. + /// + /// Returns whether the predicate was newly inserted. That is: + /// - If the set did not previously contain this predicate, `true` is returned. + /// - If the set already contained this predicate, `false` is returned, + /// and the set is not modified: original predicate is not replaced, + /// and the predicate passed as argument is dropped. pub fn insert(&mut self, pred: ty::Predicate<'tcx>) -> bool { // We have to be careful here because we want //