diff --git a/doc/go1.html b/doc/go1.html index 34e4f9cd843..77bde0adac0 100644 --- a/doc/go1.html +++ b/doc/go1.html @@ -563,16 +563,16 @@ Several packages have moved under exp at the time of Go 1's release
  • http/spdy
    • +

    +All these packages are available under the same names, with the prefix exp/: exp/ebnf etc. +

    +

    Also, the utf8.String type has been moved to its own package, exp/utf8string.

    -All these packages are available under the same names, with exp/ prefixed: exp/ebnf etc. -

    - -

    -Also, the gotype command now resides in exp/gotype, while +Finally, the gotype command now resides in exp/gotype, while ebnflint is now in exp/ebnflint

    @@ -850,6 +850,32 @@ to be implemented in the future. No changes will be needed.

    +

    The flag package

    + +

    +In Go 1, the interface flag.Value has changed slightly. +The Set method now returns an error instead of +a bool to indicate success or failure. +

    + +

    +There is also a new kind of flag, Duration, to support argument +values specifying time intervals. +Values for such flags must be given units, just as time.Duration +formats them: 10s, 1h30m, etc. +

    + +
    var timeout = flag.Duration("timeout", 30*time.Second, "how long to wait for completion")
    + +

    +Updating: +Programs that implement their own flags will need minor manual fixes to update their +Set methods. +The Duration flag is new and affects no existing code. +

    + +

    The go/* packages

    @@ -914,7 +940,6 @@ compiler will reject incorrect uses. Templates used in conjuction with any of th to run-time errors.

    -

    The hash package

    @@ -1064,6 +1089,20 @@ and os.FileMode API. Code that needs system-specific file details will need to be updated by hand.

    +

    The runtime package

    + +

    +The runtime package in Go 1 includes a new niladic function, +runtime.NumCPU, that returns the number of CPUs available +for parallel execution, as reported by the operating system kernel. +Its value can inform the setting of GOMAXPROCS. +

    + +

    +Updating: +No existing code is affected. +

    +

    The strconv package

    @@ -1159,6 +1198,35 @@ a cast that must be added by hand; gofix will warn about it.

    +

    The testing package

    + +

    +The testing package has a type, B, passed as an argument to benchmark functions. +In Go 1, B has new methods, analogous to those of T, enabling +logging and failure reporting. +

    + +
    func BenchmarkSprintf(b *testing.B) {
+    // Verify correctness before running benchmark.
+    b.StopTimer()
+    got := fmt.Sprintf("%x", 23)
+    const expect = "17"
+    if expect != got {
+        b.Fatalf("expected %q; got %q", expect, got)
+    }
+    b.StartTimer()
+    for i := 0; i < b.N; i++ {
+        fmt.Sprintf("%x", 23)
+    }
+}
    + +

    +Updating: +Existing code is unaffected, although benchmarks that use println +or panic should be updated to the new interface. +

    +

    The go command

    Packaged releases

    diff --git a/doc/go1.tmpl b/doc/go1.tmpl index 0518d081392..51dd0baca88 100644 --- a/doc/go1.tmpl +++ b/doc/go1.tmpl @@ -487,16 +487,16 @@ Several packages have moved under exp at the time of Go 1's release
  • http/spdy
    • +

    +All these packages are available under the same names, with the prefix exp/: exp/ebnf etc. +

    +

    Also, the utf8.String type has been moved to its own package, exp/utf8string.

    -All these packages are available under the same names, with exp/ prefixed: exp/ebnf etc. -

    - -

    -Also, the gotype command now resides in exp/gotype, while +Finally, the gotype command now resides in exp/gotype, while ebnflint is now in exp/ebnflint

    @@ -754,6 +754,31 @@ to be implemented in the future. No changes will be needed.

    +

    The flag package

    + +

    +In Go 1, the interface flag.Value has changed slightly. +The Set method now returns an error instead of +a bool to indicate success or failure. +

    + +

    +There is also a new kind of flag, Duration, to support argument +values specifying time intervals. +Values for such flags must be given units, just as time.Duration +formats them: 10s, 1h30m, etc. +

    + +{{code "progs/go1.go" `/timeout/`}} + +

    +Updating: +Programs that implement their own flags will need minor manual fixes to update their +Set methods. +The Duration flag is new and affects no existing code. +

    + +

    The go/* packages

    @@ -818,7 +843,6 @@ compiler will reject incorrect uses. Templates used in conjuction with any of th to run-time errors.

    -

    The hash package

    @@ -968,6 +992,20 @@ and os.FileMode API. Code that needs system-specific file details will need to be updated by hand.

    +

    The runtime package

    + +

    +The runtime package in Go 1 includes a new niladic function, +runtime.NumCPU, that returns the number of CPUs available +for parallel execution, as reported by the operating system kernel. +Its value can inform the setting of GOMAXPROCS. +

    + +

    +Updating: +No existing code is affected. +

    +

    The strconv package

    @@ -1063,6 +1101,22 @@ a cast that must be added by hand; gofix will warn about it.

    +

    The testing package

    + +

    +The testing package has a type, B, passed as an argument to benchmark functions. +In Go 1, B has new methods, analogous to those of T, enabling +logging and failure reporting. +

    + +{{code "progs/go1.go" `/func.*Benchmark/` `/^}/`}} + +

    +Updating: +Existing code is unaffected, although benchmarks that use println +or panic should be updated to the new interface. +

    +

    The go command

    Packaged releases

    diff --git a/doc/progs/go1.go b/doc/progs/go1.go index 0eccca321b9..0348aa315ef 100644 --- a/doc/progs/go1.go +++ b/doc/progs/go1.go @@ -8,13 +8,16 @@ package main import ( "errors" + "flag" "fmt" "log" + "testing" "time" "unicode" ) func main() { + flag.Parse() stringAppend() mapDelete() mapIteration() @@ -26,6 +29,8 @@ func main() { timePackage() } +var timeout = flag.Duration("timeout", 30*time.Second, "how long to wait for completion") + func mapDelete() { m := map[string]int{"7": 7, "23": 23} k := "7" @@ -187,3 +192,17 @@ func init() { go initializationFunction(c) PackageGlobal = <-c } + +func BenchmarkSprintf(b *testing.B) { + // Verify correctness before running benchmark. + b.StopTimer() + got := fmt.Sprintf("%x", 23) + const expect = "17" + if expect != got { + b.Fatalf("expected %q; got %q", expect, got) + } + b.StartTimer() + for i := 0; i < b.N; i++ { + fmt.Sprintf("%x", 23) + } +}