type interval []time.Duration

// String is the method to format the flag's value, part of the flag.Value interface.
// The String method's output will be used in diagnostics.
func (i *interval) String() string {
	return fmt.Sprint(*i)
}

// Set is the method to set the flag value, part of the flag.Value interface.
// Set's argument is a string to be parsed to set the flag.

	encoded := base64.StdEncoding.EncodeToString([]byte(msg))
	fmt.Println(encoded)
	decoded, err := base64.StdEncoding.DecodeString(encoded)
	if err != nil {
		fmt.Println("decode error:", err)
		return
	}
	fmt.Println(string(decoded))
	// Output:
	// SGVsbG8sIOS4lueVjA==
	// Hello, 世界
}

func ExampleEncoding_EncodeToString() {
	data := []byte("any + old & data")
	str := base64.StdEncoding.EncodeToString(data)
	fmt.Println(str)

	// Output:
	// context deadline exceeded
}

// This example demonstrates how a value can be passed to the context
// and also how to retrieve it if it exists.
func ExampleWithValue() {
	type favContextKey string

	f := func(ctx context.Context, k favContextKey) {
		if v := ctx.Value(k); v != nil {
			fmt.Println("found value:", v)
			return
		}
		fmt.Println("key not found:", k)
	}

	vs := []constant.Value{
		constant.MakeString("Z"),
		constant.MakeString("bacon"),
		constant.MakeString("go"),
		constant.MakeString("Frame"),
		constant.MakeString("defer"),
		constant.MakeFromLiteral(`"a"`, token.STRING, 0),
	}

	slices.SortFunc(vs, func(a, b constant.Value) int {
		if constant.Compare(a, token.LSS, b) {
			return -1
		}
		if constant.Compare(a, token.GTR, b) {
			return +1
		}
		return 0

		}
		fmt.Printf("\n")
	}
	// Output:
	// json.Delim: { (more)
	// string: Message (more)
	// string: Hello (more)
	// string: Array (more)
	// json.Delim: [ (more)
	// float64: 1 (more)
	// float64: 2 (more)
	// float64: 3
	// json.Delim: ] (more)
	// string: Null (more)
	// <nil>: <nil> (more)
	// string: Number (more)
	// float64: 1.234
	// json.Delim: }
}

	f, err := parser.ParseFile(fset, "src.go", src, 0)
	if err != nil {
		panic(err)
	}

	// Inspect the AST and print all identifiers and literals.
	ast.Inspect(f, func(n ast.Node) bool {
		var s string
		switch x := n.(type) {
		case *ast.BasicLit:
			s = x.Value
		case *ast.Ident:
			s = x.Name
		}
		if s != "" {
			fmt.Printf("%s:\t%s\n", fset.Position(n.Pos()), s)
		}
		return true
	})

import (
	"errors"
	"fmt"
	"io/fs"
	"os"
	"time"
)

// MyError is an error implementation that includes a time and message.
type MyError struct {
	When time.Time
	What string
}

func (e MyError) Error() string {
	return fmt.Sprintf("%v: %v", e.When, e.What)
}

func oops() error {
	return MyError{
		time.Date(1989, 3, 15, 22, 30, 0, 0, time.UTC),
		"the file system has gone away",
	}
}

	//
	// A long time ago in a galaxy far, far away...
}

func ExampleReader_Multistream() {
	var buf bytes.Buffer
	zw := gzip.NewWriter(&buf)

	var files = []struct {
		name    string
		comment string
		modTime time.Time
		data    string
	}{
		{"file-1.txt", "file-header-1", time.Date(2006, time.February, 1, 3, 4, 5, 0, time.UTC), "Hello Gophers - 1"},