go stringer 源码

  • 2022-07-15
  • 浏览 (934)

golang stringer 代码

文件路径:/test/typeparam/stringer.go

// run

// 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.

// Test method calls on type parameters

package main

import (
	"fmt"
	"reflect"
	"strconv"
)

// Simple constraint
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 myint int

func (i myint) String() string {
	return strconv.Itoa(int(i))
}

// Constraint with an embedded interface, but still only requires String()
type Stringer2 interface {
	CanBeStringer2() int
	SubStringer2
}

type SubStringer2 interface {
	CanBeSubStringer2() int
	String() string
}

func stringify2[T Stringer2](s []T) (ret []string) {
	for _, v := range s {
		ret = append(ret, v.String())
	}
	return ret
}

func (myint) CanBeStringer2() int {
	return 0
}

func (myint) CanBeSubStringer2() int {
	return 0
}

// Test use of method values that are not called
func stringify3[T Stringer](s []T) (ret []string) {
	for _, v := range s {
		f := v.String
		ret = append(ret, f())
	}
	return ret
}

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))
	}

	got = stringify2(x)
	if !reflect.DeepEqual(got, want) {
		panic(fmt.Sprintf("got %s, want %s", got, want))
	}

	got = stringify3(x)
	if !reflect.DeepEqual(got, want) {
		panic(fmt.Sprintf("got %s, want %s", got, want))
	}
}

相关信息

go 源码目录

相关文章

go absdiff 源码

go absdiff2 源码

go absdiff3 源码

go absdiffimp 源码

go absdiffimp2 源码

go adder 源码

go aliasimp 源码

go append 源码

go boundmethod 源码

go builtins 源码

0  赞