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// run -gcflags=-G=3
// Copyright 2021 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.
// This test illustrates how a type bound method (String below) can be implemented
// either by a concrete type (myint below) or a instantiated generic type
// (StringInt[myint] below).
package main
import (
"fmt"
"reflect"
"strconv"
)
type myint int
//go:noinline
func (m myint) String() string {
return strconv.Itoa(int(m))
}
type Stringer interface {
String() string
}
func stringify[T Stringer](s []T) (ret []string) {
for _, v := range s {
ret = append(ret, v.String())
}
return ret
}
type StringInt[T any] T
//go:noinline
func (m StringInt[T]) String() string {
return "aa"
}
func main() {
x := []myint{myint(1), myint(2), myint(3)}
got := stringify(x)
want := []string{"1", "2", "3"}
if !reflect.DeepEqual(got, want) {
panic(fmt.Sprintf("got %s, want %s", got, want))
}
x2 := []StringInt[myint]{StringInt[myint](1), StringInt[myint](2), StringInt[myint](3)}
got2 := stringify(x2)
want2 := []string{"aa", "aa", "aa"}
if !reflect.DeepEqual(got2, want2) {
panic(fmt.Sprintf("got %s, want %s", got2, want2))
}
}
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