From 84af684b48d0380759f0722207bb6132a56ed61c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Esteban=20K=C3=BCber?= <esteban@kuber.com.ar>
Date: Wed, 17 Apr 2019 16:42:52 -0700
Subject: [PATCH] review comment: add extra doc

---
 src/librustc_typeck/check/op.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/librustc_typeck/check/op.rs b/src/librustc_typeck/check/op.rs
index 46c81d34d1b6..b93ed2426b70 100644
--- a/src/librustc_typeck/check/op.rs
+++ b/src/librustc_typeck/check/op.rs
@@ -430,6 +430,8 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
         (lhs_ty, rhs_ty, return_ty)
     }
 
+    /// If one of the types is an uncalled function and calling it would yield the other type,
+    /// suggest calling the function. Returns wether a suggestion was given.
     fn add_type_neq_err_label(
         &self,
         err: &mut errors::DiagnosticBuilder<'_>,
@@ -438,7 +440,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
         other_ty: Ty<'tcx>,
         op: hir::BinOp,
         is_assign: IsAssign,
-    ) -> bool {
+    ) -> bool /* did we suggest to call a function because of missing parenthesis? */ {
         err.span_label(span, ty.to_string());
         if let FnDef(def_id, _) = ty.sty {
             let source_map = self.tcx.sess.source_map();