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| // Copyright 2018 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.
|
| package fmt_test
|
| import (
| "fmt"
| )
|
| // Address has a City, State and a Country.
| type Address struct {
| City string
| State string
| Country string
| }
|
| // Person has a Name, Age and Address.
| type Person struct {
| Name string
| Age uint
| Addr *Address
| }
|
| // GoString makes Person satisfy the GoStringer interface.
| // The return value is valid Go code that can be used to reproduce the Person struct.
| func (p Person) GoString() string {
| if p.Addr != nil {
| return fmt.Sprintf("Person{Name: %q, Age: %d, Addr: &Address{City: %q, State: %q, Country: %q}}", p.Name, int(p.Age), p.Addr.City, p.Addr.State, p.Addr.Country)
| }
| return fmt.Sprintf("Person{Name: %q, Age: %d}", p.Name, int(p.Age))
| }
|
| func ExampleGoStringer() {
| p1 := Person{
| Name: "Warren",
| Age: 31,
| Addr: &Address{
| City: "Denver",
| State: "CO",
| Country: "U.S.A.",
| },
| }
| // If GoString() wasn't implemented, the output of `fmt.Printf("%#v", p1)` would be similar to
| // Person{Name:"Warren", Age:0x1f, Addr:(*main.Address)(0x10448240)}
| fmt.Printf("%#v\n", p1)
|
| p2 := Person{
| Name: "Theia",
| Age: 4,
| }
| // If GoString() wasn't implemented, the output of `fmt.Printf("%#v", p2)` would be similar to
| // Person{Name:"Theia", Age:0x4, Addr:(*main.Address)(nil)}
| fmt.Printf("%#v\n", p2)
|
| // Output:
| // Person{Name: "Warren", Age: 31, Addr: &Address{City: "Denver", State: "CO", Country: "U.S.A."}}
| // Person{Name: "Theia", Age: 4}
| }
|
|
