From 0cab7d52d5ffaa23f31dfcabf61662a6581d1edb Mon Sep 17 00:00:00 2001
From: Rob Pike <r@golang.org>
Date: Fri, 7 Sep 2012 09:11:39 -0700
Subject: [PATCH] faq: another way to solve the closure/variable/range
 complaint It's easier just to declare a new variable.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/6501103
---
 doc/go_faq.html | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/doc/go_faq.html b/doc/go_faq.html
index 8264e1940a8..ea6edc37e90 100644
--- a/doc/go_faq.html
+++ b/doc/go_faq.html
@@ -1220,8 +1220,9 @@ but <code>v</code> may have been modified since the goroutine was launched.
 </p>
 
 <p>
-To bind the value of <code>v</code> to each closure as they are launched, one
-could modify the inner loop to read:
+To bind the current value of <code>v</code> to each closure as it is launched, one
+must modify the inner loop to create a new variable each iteration.
+One way is to pass the variable as an argument to the closure:
 </p>
 
 <pre>
@@ -1239,6 +1240,21 @@ anonymous function. That value is then accessible inside the function as
 the variable <code>u</code>.
 </p>
 
+<p>
+Even easier is just to create a new variable, using a declaration style that may
+seem odd but works fine in Go:
+</p>
+
+<pre>
+    for _, v := range values {
+        <b>v := v</b> // create a new 'v'.
+        go func() {
+            fmt.Println(<b>v</b>)
+            done &lt;- true
+        }()
+    }
+</pre>
+
 <h2 id="Control_flow">Control flow</h2>
 
 <h3 id="Does_Go_have_a_ternary_form">