</p>
<pre><!--{{code "progs/go1.go" `/type Day struct/` `/Printf/`}}
---> // type Day struct {
- // long string
- // short string
- // }
- // Christmas := Day{"Christmas", "XMas"}
- // Thanksgiving := Day{"Thanksgiving", "Turkey"}
- // holiday := map[Day]bool {
- // Christmas: true,
- // Thanksgiving: true,
- // }
- // fmt.Printf("Christmas is a holiday: %t\n", holiday[Christmas])
+--> type Day struct {
+ long string
+ short string
+ }
+ Christmas := Day{"Christmas", "XMas"}
+ Thanksgiving := Day{"Thanksgiving", "Turkey"}
+ holiday := map[Day]bool{
+ Christmas: true,
+ Thanksgiving: true,
+ }
+ fmt.Printf("Christmas is a holiday: %t\n", holiday[Christmas])
</pre>
<p>
<h3 id="time">Time</h3>
+<p>
+One of the most sweeping changes in the Go 1 library is the
+complete redesign of the
+<a href="/pkg/time/"><code>time</code></a> package.
+Instead of an integer number of nanoseconds as an <code>int64</code>,
+and a separate <code>*time.Time</code> type to deal with human
+units such as hours and years,
+there are now two fundamental types:
+<a href="/pkg/time/#Time"><code>time.Time</code></a>
+(a value, so the <code>*</code> is gone), which represents a moment in time;
+and <a href="/pkg/time/#Duration"><code>time.Duration</code></a>,
+which represents an interval.
+Both have nanosecond resolution.
+A <code>Time</code> can represent any time into the ancient
+past and remote future, while a <code>Duration</code> can
+span plus or minus only about 290 years.
+There are methods on these types, plus a number of helpful
+predefined constant durations such as <code>time.Second</code>.
+</p>
+
+<p>
+Among the new methods are things like
+<a href="/pkg/time/#Time.Add"><code>Time.Add</code></a>,
+which adds a <code>Duration</code> to a <code>Time</code>, and
+<a href="/pkg/time/#Time.Sub"><code>Time.Sub</code></a>,
+which subtracts two <code>Times</code> to yield a <code>Duration</code>.
+</p>
+
+<p>
+The most important semantic change is that the Unix epoch (Jan 1, 1970) is now
+relevant only for those functions and methods that mention Unix:
+<a href="/pkg/time/#Unix"><code>time.Unix</code></a>
+and the <a href="/pkg/time/#Time.Unix"><code>Unix</code></a>
+and <a href="/pkg/time/#Time.UnixNano"><code>UnixNano</code></a> methods
+of the <code>Time</code> type.
+In particular,
+<a href="/pkg/time/#Now"><code>time.Now</code></a>
+returns a <code>time.Time</code> value rather than, in the old
+API, an integer nanosecond count since the Unix epoch.
+</p>
+
+<pre><!--{{code "progs/go1.go" `/sleepUntil/` `/^}/`}}
+-->// sleepUntil sleeps until the specified time. It returns immediately if it's too late.
+func sleepUntil(wakeup time.Time) {
+ now := time.Now() // A Time.
+ if !wakeup.After(now) {
+ return
+ }
+ delta := wakeup.Sub(now) // A Duration.
+ log.Printf("Sleeping for %.3fs", delta.Seconds())
+ time.Sleep(delta)
+}
+</pre>
+
+<p>
+The new types, methods, and constants have been propagated through
+all the standard packages that use time, such as <code>os</code> and
+its representation of file time stamps.
+</p>
+
+<p>
+<em>Updating</em>:
+Gofix will update many uses of the old <code>time</code> package to use the new
+types and methods, although it does not replace values such as <code>1e9</code>
+representing nanoseconds per second.
+Also, because of type changes in some of the values that arise,
+some of the expressions rewritten by gofix may require
+further hand editing; in such cases the rewrite will include
+the correct function or method for the old functionality, but
+may have the wrong type or require further analysis.
+</p>
+
<h3 id="html">The html package</h3>
<p>
<h3 id="time">Time</h3>
+<p>
+One of the most sweeping changes in the Go 1 library is the
+complete redesign of the
+<a href="/pkg/time/"><code>time</code></a> package.
+Instead of an integer number of nanoseconds as an <code>int64</code>,
+and a separate <code>*time.Time</code> type to deal with human
+units such as hours and years,
+there are now two fundamental types:
+<a href="/pkg/time/#Time"><code>time.Time</code></a>
+(a value, so the <code>*</code> is gone), which represents a moment in time;
+and <a href="/pkg/time/#Duration"><code>time.Duration</code></a>,
+which represents an interval.
+Both have nanosecond resolution.
+A <code>Time</code> can represent any time into the ancient
+past and remote future, while a <code>Duration</code> can
+span plus or minus only about 290 years.
+There are methods on these types, plus a number of helpful
+predefined constant durations such as <code>time.Second</code>.
+</p>
+
+<p>
+Among the new methods are things like
+<a href="/pkg/time/#Time.Add"><code>Time.Add</code></a>,
+which adds a <code>Duration</code> to a <code>Time</code>, and
+<a href="/pkg/time/#Time.Sub"><code>Time.Sub</code></a>,
+which subtracts two <code>Times</code> to yield a <code>Duration</code>.
+</p>
+
+<p>
+The most important semantic change is that the Unix epoch (Jan 1, 1970) is now
+relevant only for those functions and methods that mention Unix:
+<a href="/pkg/time/#Unix"><code>time.Unix</code></a>
+and the <a href="/pkg/time/#Time.Unix"><code>Unix</code></a>
+and <a href="/pkg/time/#Time.UnixNano"><code>UnixNano</code></a> methods
+of the <code>Time</code> type.
+In particular,
+<a href="/pkg/time/#Now"><code>time.Now</code></a>
+returns a <code>time.Time</code> value rather than, in the old
+API, an integer nanosecond count since the Unix epoch.
+</p>
+
+{{code "progs/go1.go" `/sleepUntil/` `/^}/`}}
+
+<p>
+The new types, methods, and constants have been propagated through
+all the standard packages that use time, such as <code>os</code> and
+its representation of file time stamps.
+</p>
+
+<p>
+<em>Updating</em>:
+Gofix will update many uses of the old <code>time</code> package to use the new
+types and methods, although it does not replace values such as <code>1e9</code>
+representing nanoseconds per second.
+Also, because of type changes in some of the values that arise,
+some of the expressions rewritten by gofix may require
+further hand editing; in such cases the rewrite will include
+the correct function or method for the old functionality, but
+may have the wrong type or require further analysis.
+</p>
+
<h3 id="html">The html package</h3>
<p>
"errors"
"fmt"
"log"
+ "time"
"unicode"
)
compositeLiterals()
runeType()
errorExample()
+ timePackage()
}
func mapDelete() {
}
}
+func f(string, int) {
+}
+
func assert(t bool) {
if !t {
log.Panic("assertion fail")
}
func structEquality() {
- // Feature not net in repo.
- // type Day struct {
- // long string
- // short string
- // }
- // Christmas := Day{"Christmas", "XMas"}
- // Thanksgiving := Day{"Thanksgiving", "Turkey"}
- // holiday := map[Day]bool {
- // Christmas: true,
- // Thanksgiving: true,
- // }
- // fmt.Printf("Christmas is a holiday: %t\n", holiday[Christmas])
+ type Day struct {
+ long string
+ short string
+ }
+ Christmas := Day{"Christmas", "XMas"}
+ Thanksgiving := Day{"Thanksgiving", "Turkey"}
+ holiday := map[Day]bool{
+ Christmas: true,
+ Thanksgiving: true,
+ }
+ fmt.Printf("Christmas is a holiday: %t\n", holiday[Christmas])
}
func compositeLiterals() {
}
}
-func f(string, int) {
+// sleepUntil sleeps until the specified time. It returns immediately if it's too late.
+func sleepUntil(wakeup time.Time) {
+ now := time.Now() // A Time.
+ if !wakeup.After(now) {
+ return
+ }
+ delta := wakeup.Sub(now) // A Duration.
+ log.Printf("Sleeping for %.3fs", delta.Seconds())
+ time.Sleep(delta)
+}
+
+func timePackage() {
+ sleepUntil(time.Now().Add(123 * time.Millisecond))
}
func initializationFunction(c chan int) {