Method Last

script.go:765–786

Last produces only the last n lines of the pipe's contents, or all the lines if there are less than n. If n is zero or negative, there is no output at all.

(n int)

// if there are less than n. If n is zero or negative, there is no output at
// all.
func (p *Pipe) Last(n int) *Pipe {
	if p.Error() != nil {
		return p
	}
	if n <= 0 {
		return NewPipe()
	}
	return p.Filter(func(r io.Reader, w io.Writer) error {
		scanner := newScanner(r)
		input := ring.New(n)
		for scanner.Scan() {
			input.Value = scanner.Text()
			input = input.Next()
		}
		input.Do(func(p interface{}) {
			if p != nil {
				fmt.Fprintln(w, p)
			}
		})
		return scanner.Err()
	})
}

// Match produces only the input lines that contain the string s.
func (p *Pipe) Match(s string) *Pipe {