From 63ecc84562462830d08f1842fcf9b4fc3e35f754 Mon Sep 17 00:00:00 2001
From: Marijn Haverbeke <marijnh@gmail.com>
Date: Thu, 15 Sep 2011 10:12:09 +0200
Subject: [PATCH] Also handle fail and put in print_maybe_parens_discrim

Closes #920
---
 src/comp/syntax/print/pprust.rs | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/comp/syntax/print/pprust.rs b/src/comp/syntax/print/pprust.rs
index 6d571d61d14..667f1255fde 100644
--- a/src/comp/syntax/print/pprust.rs
+++ b/src/comp/syntax/print/pprust.rs
@@ -594,8 +594,11 @@ fn print_possibly_embedded_block(s: ps, blk: ast::blk, embedded: embed_type,
 // ret and fail, without arguments cannot appear is the discriminant of if,
 // alt, do, & while unambiguously without being parenthesized
 fn print_maybe_parens_discrim(s: ps, e: @ast::expr) {
-    let disambig =
-        alt e.node { ast::expr_ret(option::none.) { true } _ { false } };
+    let disambig = alt e.node {
+      ast::expr_ret(none.) | ast::expr_put(none.) |
+      ast::expr_fail(none.) { true }
+      _ { false }
+    };
     if disambig { popen(s) }
     print_expr(s, e);
     if disambig { pclose(s) }