time: clarify why timer.Stop and ticker.Stop don't close the channel

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/6818106

diff --git a/src/pkg/time/sleep.go b/src/pkg/time/sleep.go
index 27820b0eaa76ffbb258c5429d957e03b2604929a..657e25410312767912b0f7a9b921086e20e7989f 100644 (file)
--- a/src/pkg/time/sleep.go
+++ b/src/pkg/time/sleep.go
@@ -36,6 +36,8 @@ type Timer struct {
 // Stop prevents the Timer from firing.
 // It returns true if the call stops the timer, false if the timer has already
 // expired or stopped.
+// Stop does not close the channel, to prevent a read from the channel succeeding
+// incorrectly.
 func (t *Timer) Stop() (ok bool) {
        return stopTimer(&t.r)
 }

diff --git a/src/pkg/time/tick.go b/src/pkg/time/tick.go
index 8e435590484465a19881abf328cb8c84587de4e9..b92c339c02a21ac7cab801b4361181ae6c73ba1d 100644 (file)
--- a/src/pkg/time/tick.go
+++ b/src/pkg/time/tick.go
@@ -39,6 +39,8 @@ func NewTicker(d Duration) *Ticker {
 }
 
 // Stop turns off a ticker.  After Stop, no more ticks will be sent.
+// Stop does not close the channel, to prevent a read from the channel succeeding
+// incorrectly.
 func (t *Ticker) Stop() {
        stopTimer(&t.r)
 }