From 3dc38fbc9115f0e8cf61848938e05e1964ee29bf Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Le=C3=B3n=20Orell=20Valerian=20Liehr?= Date: Fri, 17 Feb 2023 16:55:07 +0100 Subject: [PATCH] Switch from for-loop to filter_map --- .../rustc_hir_analysis/src/astconv/mod.rs | 53 +++++++++---------- 1 file changed, 26 insertions(+), 27 deletions(-) diff --git a/compiler/rustc_hir_analysis/src/astconv/mod.rs b/compiler/rustc_hir_analysis/src/astconv/mod.rs index 43db8af7bac8..c8ff609dea55 100644 --- a/compiler/rustc_hir_analysis/src/astconv/mod.rs +++ b/compiler/rustc_hir_analysis/src/astconv/mod.rs @@ -2232,41 +2232,40 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { let param_env = tcx.param_env(block.owner.to_def_id()); let cause = ObligationCause::misc(span, block.owner.def_id); let mut fulfillment_errors = Vec::new(); - let mut applicable_candidates = Vec::new(); + let mut applicable_candidates: Vec<_> = candidates + .iter() + .filter_map(|&(impl_, (assoc_item, def_scope))| { + let ocx = ObligationCtxt::new(&infcx); - for &(impl_, (assoc_item, def_scope)) in &candidates { - let ocx = ObligationCtxt::new(&infcx); + let impl_ty = tcx.type_of(impl_); + let impl_substs = self.fresh_item_substs(impl_, &infcx); + let impl_ty = impl_ty.subst(tcx, impl_substs); + let impl_ty = ocx.normalize(&cause, param_env, impl_ty); - let impl_ty = tcx.type_of(impl_); - let impl_substs = self.fresh_item_substs(impl_, &infcx); - let impl_ty = impl_ty.subst(tcx, impl_substs); - let impl_ty = ocx.normalize(&cause, param_env, impl_ty); + // Check that the Self-types can be related. + // FIXME(fmease): Should we use `eq` here? + ocx.sup(&ObligationCause::dummy(), param_env, impl_ty, self_ty).ok()?; - // Check that the Self-types can be related. - // FIXME(fmease): Should we use `eq` here? - if ocx.sup(&ObligationCause::dummy(), param_env, impl_ty, self_ty).is_err() { - continue; - } + // Check whether the impl imposes obligations we have to worry about. + let impl_bounds = tcx.predicates_of(impl_); + let impl_bounds = impl_bounds.instantiate(tcx, impl_substs); - // Check whether the impl imposes obligations we have to worry about. - let impl_bounds = tcx.predicates_of(impl_); - let impl_bounds = impl_bounds.instantiate(tcx, impl_substs); + let impl_bounds = ocx.normalize(&cause, param_env, impl_bounds); - let impl_bounds = ocx.normalize(&cause, param_env, impl_bounds); + let impl_obligations = + traits::predicates_for_generics(|_, _| cause.clone(), param_env, impl_bounds); - let impl_obligations = - traits::predicates_for_generics(|_, _| cause.clone(), param_env, impl_bounds); + ocx.register_obligations(impl_obligations); - ocx.register_obligations(impl_obligations); + let errors = ocx.select_where_possible(); + if !errors.is_empty() { + fulfillment_errors = errors; + return None; + } - let errors = ocx.select_where_possible(); - if !errors.is_empty() { - fulfillment_errors = errors; - continue; - } - - applicable_candidates.push((assoc_item, def_scope)); - } + Some((assoc_item, def_scope)) + }) + .collect(); if applicable_candidates.len() > 1 { return Err(self.complain_about_ambiguous_inherent_assoc_type(