src/cmd/internal/bio/must.go

// Copyright 2016 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 bio

import (
	"io"
	"log"
)

// MustClose closes Closer c and calls log.Fatal if it returns a non-nil error.
func MustClose(c io.Closer) {
	if err := c.Close(); err != nil {
		log.Fatal(err)
	}
}

// MustWriter returns a Writer that wraps the provided Writer,
// except that it calls log.Fatal instead of returning a non-nil error.
func MustWriter(w io.Writer) io.Writer {
	return mustWriter{w}
}

type mustWriter struct {
	w io.Writer
}

func (w mustWriter) Write(b []byte) (int, error) {
	n, err := w.w.Write(b)
	if err != nil {
		log.Fatal(err)
	}
	return n, nil
}

func (w mustWriter) WriteString(s string) (int, error) {
	n, err := io.WriteString(w.w, s)
	if err != nil {
		log.Fatal(err)
	}
	return n, nil
}