lbl/README.md

Process stdin, line by line, sort of like AWK but 100% JS

# lbl [![NPM version][npm-image]][npm-url] [![Build Status][travis-image]][travis-url] [![Dependency Status][daviddm-image]][daviddm-url]

> Process stdin, line by line, sort of like AWK but 100% JS

## Prerequisites

- There are a couple of handy globals available
  - `$` is an alias for `global`
  - `log` is an alias for `console.log`
  - `chalk` is available for adding color to ouput

## Installation

```sh
$ npm install lbl --global
```

## Usage

```sh
Usage

  $ lbl <Options> <STDIN>

Options

  # Pass processing functions on CLI
  -a, --after     function to run after processing lines [optional]
  -b, --before    function to run before processing lines [optional]
  -e, --each      function to run on each line [required]

  # Or, use a node module file with processing functions:
  # before(), after(), each()
  -r, --require   module file with functions

  -h, --help      show this usage info
  --version       show the current version installed

Examples

  $ cat ./data/x.file | lbl -r ./scripts/X.js
  <<BEGIN>>
  > XX
  > Matched 1 from 3

  $ printf 'x\\nXX\\nxXx' | lbl -e 'x => { n++; if (x.match(/^X/)) { log(chalk.yellow('> ') + x); f++; } }' -b '() => { $.n = 0; $.f = 0; log('<<BEGIN>>'); }' -a '() => { log('> Matched ' + f + ' from ' + n); }'
  <<BEGIN>>
  > XX
  > Matched 1 from 3
```

### Sample Module File

```js
'use strict';
/* global $, log, chalk, n:true, f:true */

module.exports = {
  each: x => {
    n++;
    if (x.match(/^X/)) {
      log(chalk.yellow('> ') + x);
      f++;
    }
  },
  before: () => {
    $.n = 0;
    $.f = 0;
    log('<<BEGIN>>');
  },
  after: () => {
    log('> Matched ' + f + ' from ' + n);
  }
};
```

## License

ISC © [Buster Collings]()

[npm-image]: https://badge.fury.io/js/lbl.svg
[npm-url]: https://npmjs.org/package/lbl
[travis-image]: https://travis-ci.org/busterc/lbl.svg?branch=master
[travis-url]: https://travis-ci.org/busterc/lbl
[daviddm-image]: https://david-dm.org/busterc/lbl.svg?theme=shields.io
[daviddm-url]: https://david-dm.org/busterc/lbl