type osError struct {
	err error
}

func (b *Writer) write0(buf []byte) {
	n, err := b.output.Write(buf)
	if n != len(buf) && err == nil {
		err = io.ErrShortWrite
	}
	if err != nil {
		panic(osError{err})
	}
}

func (b *Writer) writeN(src []byte, n int) {
	for n > len(src) {
		b.write0(src)
		n -= len(src)
	}
	b.write0(src[0:n])
}

var (
	newline = []byte{'\n'}

}

// NewWriter returns a new Writer that writes to w.
func NewWriter(w io.Writer) *Writer {
	return &Writer{
		Comma: ',',
		w:     bufio.NewWriter(w),
	}
}

// Write writes a single CSV record to w along with any necessary quoting.
// A record is a slice of strings with each string being one field.
// Writes are buffered, so [Writer.Flush] must eventually be called to ensure

}

// Write encodes p using quoted-printable encoding and writes it to the
// underlying [io.Writer]. It limits line length to 76 characters. The encoded
// bytes are not necessarily flushed until the [Writer] is closed.
func (w *Writer) Write(p []byte) (n int, err error) {
	for i, b := range p {
		switch {
		// Simple writes are done in batch.
		case b >= '!' && b <= '~' && b != '=':
			continue

	invalidEntry = 0
)

// Writer is an LZW compressor. It writes the compressed form of the data
// to an underlying writer (see [NewWriter]).
type Writer struct {
	// w is the writer that compressed bytes are written to.
	w writer
	// litWidth is the width in bits of literal codes.
	litWidth uint
	// order, write, bits, nBits and width are the state for

)

// A Writer takes data written to it and writes the compressed
// form of that data to an underlying writer (see NewWriter).
type Writer struct {
	w           io.Writer
	level       int
	dict        []byte
	compressor  *flate.Writer
	digest      hash.Hash32
	err         error
	scratch     [4]byte
	wroteHeader bool
}

// NewWriter creates a new Writer.

// NewWriter creates a new byte format writer.
func NewWriter(w io.Writer, v version.Version) (*Writer, error) {
	_, err := version.WriteHeader(w, v)
	return &Writer{w: w, v: v, specs: v.Specs()}, err
}

// WriteEvent writes a single event to the trace wire format stream.
func (w *Writer) WriteEvent(e Event) error {
	// Check version.
	if e.Version != w.v {

import "io"

// TruncateWriter returns a Writer that writes to w
// but stops silently after n bytes.
func TruncateWriter(w io.Writer, n int64) io.Writer {
	return &truncateWriter{w, n}
}

type truncateWriter struct {
	w io.Writer
	n int64
}

func (t *truncateWriter) Write(p []byte) (n int, err error) {
	if t.n <= 0 {
		return len(p), nil
	}
	// real write
	n = len(p)
	if int64(n) > t.n {
		n = int(t.n)

	"errors"
	"fmt"
	"io"
	"net/textproto"
	"slices"
	"strings"
)

// A Writer generates multipart messages.
type Writer struct {
	w        io.Writer
	boundary string
	lastpart *part
}

// NewWriter returns a new multipart [Writer] with a random boundary,
// writing to w.
func NewWriter(w io.Writer) *Writer {
	return &Writer{
		w:        w,
		boundary: randomBoundary(),
	}
}

package textproto

import (
	"bufio"
	"fmt"
	"io"
)

// A Writer implements convenience methods for writing
// requests or responses to a text protocol network connection.
type Writer struct {
	W   *bufio.Writer
	dot *dotWriter
}

// NewWriter returns a new [Writer] writing to w.
func NewWriter(w *bufio.Writer) *Writer {
	return &Writer{W: w}
}

var crnl = []byte{'\r', '\n'}

	"path"
	"slices"
	"strings"
	"time"
)

// Writer provides sequential writing of a tar archive.
// [Writer.WriteHeader] begins a new file with the provided [Header],
// and then Writer can be treated as an io.Writer to supply that file's data.
type Writer struct {
	w    io.Writer
	pad  int64      // Amount of padding to write after current file entry
	curr fileWriter // Writer for current file entry