mirror of
https://github.com/golang/go
synced 2024-11-22 06:44:40 -07:00
60 lines
1017 B
Go
60 lines
1017 B
Go
// $G $D/$F.go && $L $F.$A && ./$A.out
|
|
|
|
// 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 main
|
|
|
|
// test range over channels
|
|
|
|
func gen(c chan int, lo, hi int) {
|
|
for i := lo; i <= hi; i++ {
|
|
c <- i;
|
|
}
|
|
close(c);
|
|
}
|
|
|
|
func seq(lo, hi int) chan int {
|
|
c := make(chan int);
|
|
go gen(c, lo, hi);
|
|
return c;
|
|
}
|
|
|
|
func testchan() {
|
|
s := "";
|
|
for i := range seq('a', 'z') {
|
|
s += string(i);
|
|
}
|
|
if s != "abcdefghijklmnopqrstuvwxyz" {
|
|
panicln("Wanted lowercase alphabet; got", s);
|
|
}
|
|
}
|
|
|
|
// test that range over array only evaluates
|
|
// the expression after "range" once.
|
|
|
|
var nmake = 0;
|
|
func makearray() []int {
|
|
nmake++;
|
|
return []int{1,2,3,4,5};
|
|
}
|
|
|
|
func testarray() {
|
|
s := 0;
|
|
for _, v := range makearray() {
|
|
s += v;
|
|
}
|
|
if nmake != 1 {
|
|
panicln("range called makearray", nmake, "times");
|
|
}
|
|
if s != 15 {
|
|
panicln("wrong sum ranging over makearray");
|
|
}
|
|
}
|
|
|
|
func main() {
|
|
testchan();
|
|
testarray();
|
|
}
|