From: Shenghou Ma <minux.ma@gmail.com>
Date: Mon, 17 Dec 2012 15:37:02 +0000 (+0800)
Subject: os: fix docs for Expand
X-Git-Tag: go1.1rc2~1609
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=57ae2e7371de9c7c5c2f6314baf95ca8b94a61d8;p=gostls13.git

os: fix docs for Expand
there is no concept of “undefined” variables for Expand。

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/6946063
---

diff --git a/src/pkg/os/env.go b/src/pkg/os/env.go
index eb265f2413..db7fc72b8a 100644
--- a/src/pkg/os/env.go
+++ b/src/pkg/os/env.go
@@ -9,7 +9,7 @@ package os
 import "syscall"
 
 // Expand replaces ${var} or $var in the string based on the mapping function.
-// Invocations of undefined variables are replaced with the empty string.
+// For example, os.ExpandEnv(s) is equivalent to os.Expand(s, os.Getenv).
 func Expand(s string, mapping func(string) string) string {
 	buf := make([]byte, 0, 2*len(s))
 	// ${} is all ASCII, so bytes are fine for this operation.