code review 5715046: sync: add Once example

sync: add Once example

[dvyukov, 2012-03-01 12:00:42]

Hello golang-dev@googlegroups.com,

I'd like you to review this change to
https://go.googlecode.com/hg/

[rsc, 2012-03-01 16:19:00]

This is an unfortunate example, because it allocates the closure on each run.
Better to use a function.

[bradfitzgoog, 2012-03-01 17:17:08]

Does it have to allocate though? It doesn't close over anything and funcs
can no longer ==. The compiler could generate this once, right?
On Mar 1, 2012 8:19 AM, "Russ Cox" <rsc@golang.org> wrote:

> This is an unfortunate example, because it allocates the closure on each
> run.
> Better to use a function.
>

[rsc, 2012-03-01 17:18:23]

On Thu, Mar 1, 2012 at 12:17, Brad Fitzpatrick <bradfitz@google.com> wrote:
> Does it have to allocate though? It doesn't close over anything and funcs
> can no longer ==. The compiler could generate this once, right?

It does, now, but having to explain that distracts from the example.

[dvyukov, 2012-03-01 17:24:11]

Hello golang-dev@googlegroups.com, rsc@golang.org, bradfitz@google.com (cc:
golang-dev@googlegroups.com),

Please take another look.

[rsc, 2012-03-01 18:14:32]

LGTM

[dvyukov, 2012-03-01 18:16:25]

*** Submitted as http://code.google.com/p/go/source/detail?r=096c7653c6b5 ***

sync: add Once example

R=golang-dev, rsc, bradfitz
CC=golang-dev
http://codereview.appspot.com/5715046