From adba642a388cf14b6ffa9dd917443957c94e82fb Mon Sep 17 00:00:00 2001
From: Andre Bogus <bogusandre@gmail.com>
Date: Mon, 13 Mar 2017 23:56:27 +0100
Subject: [PATCH] fix format grammar

---
 src/libcollections/fmt.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/libcollections/fmt.rs b/src/libcollections/fmt.rs
index dfd292176d2f9..1ec1749c3aa64 100644
--- a/src/libcollections/fmt.rs
+++ b/src/libcollections/fmt.rs
@@ -306,7 +306,8 @@
 //! `%`. The actual grammar for the formatting syntax is:
 //!
 //! ```text
-//! format_string := <text> [ format <text> ] *
+//! format_string := <text> [ maybe-format <text> ] *
+//! maybe-format := '{' '{' | '}' '}' | <format>
 //! format := '{' [ argument ] [ ':' format_spec ] '}'
 //! argument := integer | identifier
 //!