From 082c03b0780b2de24b68be04e96d1596a7c5b3cf Mon Sep 17 00:00:00 2001
From: Daan Sprenkels <dsprenkels@gmail.com>
Date: Wed, 6 Jan 2016 23:58:45 +0100
Subject: libsyntax: note that `let a = (let b = something)` is invalid in
 parse_bottom_expr (parser.rs)

---
 src/libsyntax/parse/parser.rs | 6 ++++++
 1 file changed, 6 insertions(+)

(limited to 'src/libsyntax/parse/parser.rs')

diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index bfa42e76129..edb1f7eb926 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -2199,6 +2199,12 @@ impl<'a> Parser<'a> {
                         UnsafeBlock(ast::UserProvided),
                         attrs);
                 }
+                if self.eat_keyword(keywords::Let) {
+                    return Err(self.span_fatal(self.span,
+                                               "`let` is not an expression, so it cannot \
+                                                be used in this way"))
+
+                }
                 if self.eat_keyword(keywords::Return) {
                     if self.token.can_begin_expr() {
                         let e = try!(self.parse_expr());
-- 
cgit 1.4.1-3-g733a5