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      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 // Test Implicit methods for embedded types and
      8 // mixed pointer and non-pointer receivers.
      9 
     10 package main
     11 
     12 type T int
     13 
     14 var nv, np int
     15 
     16 func (t T) V() {
     17 	if t != 42 {
     18 		panic(t)
     19 	}
     20 	nv++
     21 }
     22 
     23 func (t *T) P() {
     24 	if *t != 42 {
     25 		println(t, *t)
     26 		panic("fail")
     27 	}
     28 	np++
     29 }
     30 
     31 type V interface {
     32 	V()
     33 }
     34 type P interface {
     35 	P()
     36 	V()
     37 }
     38 
     39 type S struct {
     40 	T
     41 }
     42 
     43 type SP struct {
     44 	*T
     45 }
     46 
     47 func main() {
     48 	var t T
     49 	var v V
     50 	var p P
     51 
     52 	t = 42
     53 
     54 	t.P()
     55 	t.V()
     56 
     57 	v = t
     58 	v.V()
     59 
     60 	p = &t
     61 	p.P()
     62 	p.V()
     63 
     64 	v = &t
     65 	v.V()
     66 
     67 	//	p = t	// ERROR
     68 	var i interface{} = t
     69 	if _, ok := i.(P); ok {
     70 		println("dynamic i.(P) succeeded incorrectly")
     71 		panic("fail")
     72 	}
     73 
     74 	//	println("--struct--");
     75 	var s S
     76 	s.T = 42
     77 	s.P()
     78 	s.V()
     79 
     80 	v = s
     81 	s.V()
     82 
     83 	p = &s
     84 	p.P()
     85 	p.V()
     86 
     87 	v = &s
     88 	v.V()
     89 
     90 	//	p = s	// ERROR
     91 	var j interface{} = s
     92 	if _, ok := j.(P); ok {
     93 		println("dynamic j.(P) succeeded incorrectly")
     94 		panic("fail")
     95 	}
     96 
     97 	//	println("--struct pointer--");
     98 	var sp SP
     99 	sp.T = &t
    100 	sp.P()
    101 	sp.V()
    102 
    103 	v = sp
    104 	sp.V()
    105 
    106 	p = &sp
    107 	p.P()
    108 	p.V()
    109 
    110 	v = &sp
    111 	v.V()
    112 
    113 	p = sp // not error
    114 	p.P()
    115 	p.V()
    116 
    117 	if nv != 13 || np != 7 {
    118 		println("bad count", nv, np)
    119 		panic("fail")
    120 	}
    121 }
    122