105 lines
2.1 KiB
Go
105 lines
2.1 KiB
Go
// Copyright © 2016 Alan A. A. Donovan & Brian W. Kernighan.
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// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
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// See page 108.
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// Movie prints Movies as JSON.
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package main
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import (
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"encoding/json"
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"fmt"
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"log"
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)
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//!+
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type Movie struct {
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Title string
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Year int `json:"released"`
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Color bool `json:"color,omitempty"`
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Actors []string
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}
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var movies = []Movie{
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{Title: "Casablanca", Year: 1942, Color: false,
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Actors: []string{"Humphrey Bogart", "Ingrid Bergman"}},
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{Title: "Cool Hand Luke", Year: 1967, Color: true,
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Actors: []string{"Paul Newman"}},
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{Title: "Bullitt", Year: 1968, Color: true,
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Actors: []string{"Steve McQueen", "Jacqueline Bisset"}},
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// ...
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}
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//!-
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func main() {
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{
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//!+Marshal
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data, err := json.Marshal(movies)
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if err != nil {
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log.Fatalf("JSON marshaling failed: %s", err)
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}
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fmt.Printf("%s\n", data)
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//!-Marshal
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}
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{
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//!+MarshalIndent
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data, err := json.MarshalIndent(movies, "", " ")
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if err != nil {
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log.Fatalf("JSON marshaling failed: %s", err)
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}
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fmt.Printf("%s\n", data)
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//!-MarshalIndent
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//!+Unmarshal
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var titles []struct{ Title string }
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if err := json.Unmarshal(data, &titles); err != nil {
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log.Fatalf("JSON unmarshaling failed: %s", err)
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}
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fmt.Println(titles) // "[{Casablanca} {Cool Hand Luke} {Bullitt}]"
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//!-Unmarshal
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}
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}
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/*
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//!+output
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[{"Title":"Casablanca","released":1942,"Actors":["Humphrey Bogart","Ingr
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id Bergman"]},{"Title":"Cool Hand Luke","released":1967,"color":true,"Ac
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tors":["Paul Newman"]},{"Title":"Bullitt","released":1968,"color":true,"
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Actors":["Steve McQueen","Jacqueline Bisset"]}]
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//!-output
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*/
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/*
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//!+indented
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[
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{
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"Title": "Casablanca",
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"released": 1942,
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"Actors": [
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"Humphrey Bogart",
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"Ingrid Bergman"
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]
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},
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{
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"Title": "Cool Hand Luke",
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"released": 1967,
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"color": true,
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"Actors": [
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"Paul Newman"
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]
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},
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{
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"Title": "Bullitt",
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"released": 1968,
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"color": true,
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"Actors": [
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"Steve McQueen",
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"Jacqueline Bisset"
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]
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}
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]
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//!-indented
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*/
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