From 10639d7958e951bb5478750e8fcce3eeda868304 Mon Sep 17 00:00:00 2001 From: Corey Farwell Date: Sun, 19 Feb 2017 13:12:18 -0500 Subject: [PATCH] Add early return, remove `else`, unindent. --- src/librustc/traits/error_reporting.rs | 78 +++++++++++++------------- 1 file changed, 39 insertions(+), 39 deletions(-) diff --git a/src/librustc/traits/error_reporting.rs b/src/librustc/traits/error_reporting.rs index 11a777d5fe44..c2fbccf82da9 100644 --- a/src/librustc/traits/error_reporting.rs +++ b/src/librustc/traits/error_reporting.rs @@ -708,46 +708,46 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> { let trait_ref = data.to_poly_trait_ref(); let self_ty = trait_ref.self_ty(); if predicate.references_error() { - } else { - // Typically, this ambiguity should only happen if - // there are unresolved type inference variables - // (otherwise it would suggest a coherence - // failure). But given #21974 that is not necessarily - // the case -- we can have multiple where clauses that - // are only distinguished by a region, which results - // in an ambiguity even when all types are fully - // known, since we don't dispatch based on region - // relationships. + return; + } + // Typically, this ambiguity should only happen if + // there are unresolved type inference variables + // (otherwise it would suggest a coherence + // failure). But given #21974 that is not necessarily + // the case -- we can have multiple where clauses that + // are only distinguished by a region, which results + // in an ambiguity even when all types are fully + // known, since we don't dispatch based on region + // relationships. - // This is kind of a hack: it frequently happens that some earlier - // error prevents types from being fully inferred, and then we get - // a bunch of uninteresting errors saying something like " doesn't implement Sized". It may even be true that we - // could just skip over all checks where the self-ty is an - // inference variable, but I was afraid that there might be an - // inference variable created, registered as an obligation, and - // then never forced by writeback, and hence by skipping here we'd - // be ignoring the fact that we don't KNOW the type works - // out. Though even that would probably be harmless, given that - // we're only talking about builtin traits, which are known to be - // inhabited. But in any case I just threw in this check for - // has_errors() to be sure that compilation isn't happening - // anyway. In that case, why inundate the user. - if !self.tcx.sess.has_errors() { - if - self.tcx.lang_items.sized_trait() - .map_or(false, |sized_id| sized_id == trait_ref.def_id()) - { - self.need_type_info(obligation, self_ty); - } else { - let mut err = struct_span_err!(self.tcx.sess, - obligation.cause.span, E0283, - "type annotations required: \ - cannot resolve `{}`", - predicate); - self.note_obligation_cause(&mut err, obligation); - err.emit(); - } + // This is kind of a hack: it frequently happens that some earlier + // error prevents types from being fully inferred, and then we get + // a bunch of uninteresting errors saying something like " doesn't implement Sized". It may even be true that we + // could just skip over all checks where the self-ty is an + // inference variable, but I was afraid that there might be an + // inference variable created, registered as an obligation, and + // then never forced by writeback, and hence by skipping here we'd + // be ignoring the fact that we don't KNOW the type works + // out. Though even that would probably be harmless, given that + // we're only talking about builtin traits, which are known to be + // inhabited. But in any case I just threw in this check for + // has_errors() to be sure that compilation isn't happening + // anyway. In that case, why inundate the user. + if !self.tcx.sess.has_errors() { + if + self.tcx.lang_items.sized_trait() + .map_or(false, |sized_id| sized_id == trait_ref.def_id()) + { + self.need_type_info(obligation, self_ty); + } else { + let mut err = struct_span_err!(self.tcx.sess, + obligation.cause.span, E0283, + "type annotations required: \ + cannot resolve `{}`", + predicate); + self.note_obligation_cause(&mut err, obligation); + err.emit(); } } }