interpres/example_test.go

// Copyright (c) 2026 Petr Balvín <opensource@petrbalvin.org> (https://petrbalvin.org)
// SPDX-License-Identifier: MIT

package interpres_test

import (
	"fmt"
	"log"

	"sourcedock.dev/petrbalvin/interpres/v2"
)

func ExampleParse() {
	const doc = `
title = "interpres"

[server]
host = "127.0.0.1"
port = 9090
`
	d, err := interpres.Parse([]byte(doc))
	if err != nil {
		log.Fatal(err)
	}
	for _, key := range d.Root().Keys() { // written order, not sorted
		entry, _ := d.Root().Get(key)
		fmt.Println(key, "=", entry.Value())
	}
	// Output:
	// title = interpres
	// server = map[host:127.0.0.1 port:9090]
}

func ExampleUnmarshal() {
	type Config struct {
		Host string `toml:"host"`
		Port int    `toml:"port"`
	}
	var cfg Config
	err := interpres.Unmarshal([]byte("host = \"db\"\nport = 5432\n"), &cfg)
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(cfg.Host, cfg.Port)
	// Output: db 5432
}

func ExampleMarshal() {
	type Server struct {
		Host string `toml:"host"`
		Port int    `toml:"port"`
	}
	type Config struct {
		Title  string `toml:"title"`
		Server Server `toml:"server"`
	}
	out, err := interpres.Marshal(Config{
		Title:  "demo",
		Server: Server{Host: "127.0.0.1", Port: 9090},
	})
	if err != nil {
		log.Fatal(err)
	}
	fmt.Printf("%s", out)
	// Output:
	// title = "demo"
	//
	// [server]
	// host = "127.0.0.1"
	// port = 9090
}

func ExampleDecoder() {
	var tree map[string]any
	err := interpres.NewDecoder().
		DisallowUnknownFields().
		UseNumber().
		Decode([]byte("rate = 1_000\n"), &tree)
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(tree["rate"], string(tree["rate"].(interpres.Number)))
	// Output: 1_000 1_000
}

func ExampleEncoder() {
	type Config struct {
		Title  string            `toml:"title"`
		Extras map[string]string `toml:"extras,inline"`
	}
	out, err := interpres.NewEncoder().
		Layout(interpres.LayoutKindDeclaration).
		LiteralMultiline(80).
		InlineTables(40).
		Marshal(Config{Title: "demo", Extras: map[string]string{"b": "two", "a": "one"}})
	if err != nil {
		log.Fatal(err)
	}
	fmt.Printf("%s", out)
	// Output:
	// title = "demo"
	// extras = {a = "one", b = "two"}
}