filter_countwords.go

// scriptish is a library to help you port bash scripts to Golang
//
// inspired by:
//
// - http://labix.org/pipe
// - https://github.com/bitfield/script
//
// Copyright 2019-present Ganbaro Digital Ltd
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
//   * Redistributions of source code must retain the above copyright
//     notice, this list of conditions and the following disclaimer.
//
//   * Redistributions in binary form must reproduce the above copyright
//     notice, this list of conditions and the following disclaimer in
//     the documentation and/or other materials provided with the
//     distribution.
//
//   * Neither the names of the copyright holders nor the names of his
//     contributors may be used to endorse or promote products derived
//     from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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// POSSIBILITY OF SUCH DAMAGE.

package scriptish

import (
	"strconv"
)

// CountWords counts the number of words in the pipe's stdin, and writes
// the overall count to the pipe's stdout
func CountWords(opts ...*StepOption) *SequenceStep {
	// build our Scriptish command
	return NewSequenceStep(
		func(p *Pipe) (int, error) {
			// debugging support
			Tracef("CountWords()")

			count := 0
			for range p.Stdin.ReadWords() {
				count++
			}

			TracePipeStdout("%d", count)
			p.Stdout.WriteString(strconv.Itoa(count))
			p.Stdout.WriteRune('\n')

			return StatusOkay, nil
		},
		opts...,
	)
}