1 // run 2 3 // Copyright 2009 The Go Authors. All rights reserved. 4 // Use of this source code is governed by a BSD-style 5 // license that can be found in the LICENSE file. 6 7 package main 8 9 type I interface{} 10 11 func foo1(i int) int { return i } 12 func foo2(i int32) int32 { return i } 13 func main() { 14 var i I 15 i = 1 16 var v1 = i.(int) 17 if foo1(v1) != 1 { 18 panic(1) 19 } 20 var v2 = int32(i.(int)) 21 if foo2(v2) != 1 { 22 panic(2) 23 } 24 25 shouldPanic(p1) 26 } 27 28 func p1() { 29 var i I 30 i = 1 31 var v3 = i.(int32) // This type conversion should fail at runtime. 32 if foo2(v3) != 1 { 33 panic(3) 34 } 35 } 36 37 func shouldPanic(f func()) { 38 defer func() { 39 if recover() == nil { 40 panic("function should panic") 41 } 42 }() 43 f() 44 } 45
