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Diffstat (limited to 'compiler/rustc_trait_selection/src/infer.rs')
| -rw-r--r-- | compiler/rustc_trait_selection/src/infer.rs | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/compiler/rustc_trait_selection/src/infer.rs b/compiler/rustc_trait_selection/src/infer.rs index bacb3b1b1b8..e91574fa1af 100644 --- a/compiler/rustc_trait_selection/src/infer.rs +++ b/compiler/rustc_trait_selection/src/infer.rs @@ -60,6 +60,18 @@ impl<'tcx> InferCtxt<'tcx> { /// /// Invokes `evaluate_obligation`, so in the event that evaluating /// `Ty: Trait` causes overflow, EvaluatedToAmbigStackDependent will be returned. + /// + /// `type_implements_trait` is a convenience function for simple cases like + /// + /// ```ignore (illustrative) + /// let copy_trait = infcx.tcx.require_lang_item(LangItem::Copy, span); + /// let implements_copy = infcx.type_implements_trait(copy_trait, [ty], param_env) + /// .must_apply_modulo_regions(); + /// ``` + /// + /// In most cases you should instead create an [Obligation](traits::Obligation) + /// and check whether it holds, because it properly handles higher ranked traits + /// and it is more convenient and safer when your `params` are inside a `Binder`. #[instrument(level = "debug", skip(self, params), ret)] fn type_implements_trait( &self, |