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// $G $D/$F.go && $L $F.$A && ./$A.out || echo BUG interface6
// 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.
// Interface values containing structures.
package main
import "os"
var fail int
func check(b bool, msg string) {
if (!b) {
println("failure in", msg)
fail++
}
}
type I1 interface { Get() int; Put(int) }
type S1 struct { i int }
func (p S1) Get() int { return p.i }
func (p S1) Put(i int) { p.i = i }
func f1() {
s := S1{1}
var i I1 = s
i.Put(2)
check(i.Get() == 1, "f1 i")
check(s.i == 1, "f1 s")
}
func f2() {
s := S1{1}
var i I1 = &s
i.Put(2)
check(i.Get() == 1, "f2 i")
check(s.i == 1, "f2 s")
}
func f3() {
s := &S1{1}
var i I1 = s
i.Put(2)
check(i.Get() == 1, "f3 i")
check(s.i == 1, "f3 s")
}
type S2 struct { i int }
func (p *S2) Get() int { return p.i }
func (p *S2) Put(i int) { p.i = i }
// Disallowed by restriction of values going to pointer receivers
// func f4() {
// s := S2{1}
// var i I1 = s
// i.Put(2)
// check(i.Get() == 2, "f4 i")
// check(s.i == 1, "f4 s")
// }
func f5() {
s := S2{1}
var i I1 = &s
i.Put(2)
check(i.Get() == 2, "f5 i")
check(s.i == 2, "f5 s")
}
func f6() {
s := &S2{1}
var i I1 = s
i.Put(2)
check(i.Get() == 2, "f6 i")
check(s.i == 2, "f6 s")
}
type I2 interface { Get() int64; Put(int64) }
type S3 struct { i, j, k, l int64 }
func (p S3) Get() int64 { return p.l }
func (p S3) Put(i int64) { p.l = i }
func f7() {
s := S3{1, 2, 3, 4}
var i I2 = s
i.Put(5)
check(i.Get() == 4, "f7 i")
check(s.l == 4, "f7 s")
}
func f8() {
s := S3{1, 2, 3, 4}
var i I2 = &s
i.Put(5)
check(i.Get() == 4, "f8 i")
check(s.l == 4, "f8 s")
}
func f9() {
s := &S3{1, 2, 3, 4}
var i I2 = s
i.Put(5)
check(i.Get() == 4, "f9 i")
check(s.l == 4, "f9 s")
}
type S4 struct { i, j, k, l int64 }
func (p *S4) Get() int64 { return p.l }
func (p *S4) Put(i int64) { p.l = i }
// Disallowed by restriction of values going to pointer receivers
// func f10() {
// s := S4{1, 2, 3, 4}
// var i I2 = s
// i.Put(5)
// check(i.Get() == 5, "f10 i")
// check(s.l == 4, "f10 s")
// }
func f11() {
s := S4{1, 2, 3, 4}
var i I2 = &s
i.Put(5)
check(i.Get() == 5, "f11 i")
check(s.l == 5, "f11 s")
}
func f12() {
s := &S4{1, 2, 3, 4}
var i I2 = s
i.Put(5)
check(i.Get() == 5, "f12 i")
check(s.l == 5, "f12 s")
}
func main() {
f1()
f2()
f3()
// f4()
f5()
f6()
f7()
f8()
f9()
// f10()
f11()
f12()
if fail > 0 {
os.Exit(1)
}
}
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