-// $G $F.go && $L $F.$A && ./$A.out
+// run
// 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.
+// Test simultaneous assignment.
+
package main
-var a,b,c,d,e,f,g,h,i int;
+var a, b, c, d, e, f, g, h, i int
-func
-printit()
-{
- print a,b,c,d,e,f,g,h,i,"\n";
+func printit() {
+ println(a, b, c, d, e, f, g, h, i)
}
-func
-testit() bool
-{
+func testit(permuteok bool) bool {
if a+b+c+d+e+f+g+h+i != 45 {
- print "sum does not add to 45\n";
- printit();
- panic;
+ print("sum does not add to 45\n")
+ printit()
+ return false
}
- return a == 1 &&
- b == 2 &&
- c == 3 &&
- d == 4 &&
- e == 5 &&
- f == 6 &&
- g == 7 &&
- h == 8 &&
- i == 9;
+ return permuteok ||
+ a == 1 &&
+ b == 2 &&
+ c == 3 &&
+ d == 4 &&
+ e == 5 &&
+ f == 6 &&
+ g == 7 &&
+ h == 8 &&
+ i == 9
+}
+
+func swap(x, y int) (u, v int) {
+ return y, x
}
-func main()
-{
- a = 1;
- b = 2;
- c = 3;
- d = 4;
- e = 5;
- f = 6;
- g = 7;
- h = 8;
- i = 9;
+func main() {
+ a = 1
+ b = 2
+ c = 3
+ d = 4
+ e = 5
+ f = 6
+ g = 7
+ h = 8
+ i = 9
- if !testit() { panic "init val\n"; }
+ if !testit(false) {
+ panic("init val\n")
+ }
- for z:=0; z<100; z++ {
- a,b,c,d, e,f,g,h,i = b,c,d,a, i,e,f,g,h;
+ for z := 0; z < 100; z++ {
+ a, b, c, d, e, f, g, h, i = b, c, d, a, i, e, f, g, h
- if testit() {
- if z == 19 {
- break;
- }
- print "on ", z, "th iteration\n";
- printit();
- panic;
+ if !testit(z%20 != 19) {
+ print("on ", z, "th iteration\n")
+ printit()
+ panic("fail")
}
}
- if !testit() {
- print "final val\n";
- printit();
- panic;
+ if !testit(false) {
+ print("final val\n")
+ printit()
+ panic("fail")
+ }
+
+ a, b = swap(1, 2)
+ if a != 2 || b != 1 {
+ panic("bad swap")
+ }
+
+ a, b = swap(swap(a, b))
+ if a != 2 || b != 1 {
+ panic("bad swap")
}
}