code review 5334051: runtime: add timer support, use for package time

src/pkg/time/tick.go

 // Copyright 2009 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
 package time
 
 import "errors"
 
 // A Ticker holds a synchronous channel that delivers `ticks' of a clock
 // at intervals.
 type Ticker struct {
-        C        <-chan int64 // The channel on which the ticks are delivered.
+        C <-chan int64 // The channel on which the ticks are delivered.
         r runtimeTimer
 }
 
 // NewTicker returns a new Ticker containing a channel that will
 // send the time, in nanoseconds, every ns nanoseconds.  It adjusts the
 // intervals to make up for pauses in delivery of the ticks. The value of
 // ns must be greater than zero; if not, NewTicker will panic.
 func NewTicker(ns int64) *Ticker {
         if ns <= 0 {
                 panic(errors.New("non-positive interval for NewTicker"))
         }
         // Give the channel a 1-element time buffer.
         // If the client falls behind while reading, we drop ticks
         // on the floor until the client catches up.
         c := make(chan int64, 1)
         t := &Ticker{
-                C:        c,
+                C: c,
                 r: runtimeTimer{
-                        when: Nanoseconds() + ns,
+                        when:   Nanoseconds() + ns,
                         period: ns,
-                        f: sendTime,
-                        arg: c,
+                        f:      sendTime,
+                        arg:    c,
                 },
         }
         startTimer(&t.r)
         return t
 }
 
 // Stop turns off a ticker.  After Stop, no more ticks will be sent.
 func (t *Ticker) Stop() {
         stopTimer(&t.r)
 }
 
 // Tick is a convenience wrapper for NewTicker providing access to the ticking
 // channel only.  Useful for clients that have no need to shut down the ticker.
 func Tick(ns int64) <-chan int64 {
         if ns <= 0 {
                 return nil
         }
         return NewTicker(ns).C
 }