1 // run 2 3 // Copyright 2017 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 import ( 10 "fmt" 11 "strings" 12 ) 13 14 type ET struct{} 15 16 func (*ET) Error() string { return "err" } 17 18 func main() { 19 check("false", fmt.Sprintf("(*ET)(nil) == error(nil): %v", (*ET)(nil) == error(nil))) 20 check("true", fmt.Sprintf("(*ET)(nil) != error(nil): %v", (*ET)(nil) != error(nil))) 21 22 nilET := (*ET)(nil) 23 nilError := error(nil) 24 25 check("false", fmt.Sprintf("nilET == nilError: %v", nilET == nilError)) 26 check("true", fmt.Sprintf("nilET != nilError: %v", nilET != nilError)) 27 } 28 29 func check(want, gotfull string) { 30 got := gotfull[strings.Index(gotfull, ": ")+len(": "):] 31 if got != want { 32 panic("want " + want + " got " + got + " from " + gotfull) 33 } 34 } 35
