typed/buffer.go
func (w *WriteBuffer) WriteBytes(in []byte) {
	if b := w.reserve(len(in)); b != nil {
		copy(b, in)
	}
}
func (w *WriteBuffer) WriteBytes(in []byte) {
	if b := w.reserve(len(in)); b != nil {
		copy(b, in)
	}
}
// WriteBytes writes a slice of bytes to the buffer