From 2eda013ea24c7a6209bbd3836460c5a31a18682c Mon Sep 17 00:00:00 2001
From: Matt Brubeck <mbrubeck@cs.hmc.edu>
Date: Thu, 19 Jan 2012 21:52:55 -0800
Subject: [PATCH] Add documentation about paretheses for grouping expressions

---
 doc/rust.md | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/doc/rust.md b/doc/rust.md
index ef96caed146d3..e3343304275b7 100644
--- a/doc/rust.md
+++ b/doc/rust.md
@@ -1705,6 +1705,22 @@ as
 
 Operators at the same precedence level are evaluated left-to-right.
 
+### Grouped expressions
+
+An expression enclosed in parentheses evaluates to the result of the enclosed
+expression.  Parentheses can be used to explicitly specify evaluation order
+within an expression.
+
+~~~~~~~~{.ebnf .gram}
+paren_expr : '(' expr ')' ;
+~~~~~~~~
+
+An example of a parenthesized expression:
+
+~~~~
+let x = (2 + 3) * 4;
+~~~~
+
 ### Unary copy expressions
 
 ~~~~~~~~{.ebnf .gram}