regx

[![NPM version][npm-img]][npm-url] [![Downloads][downloads-img]][npm-url] [![Tip][amazon-img]][amazon-url]

Tagged template string [regular expression][guide] compiler. Supports multiline expressions, partials, and embedded comments.

Install

$ npm install --save regx

Example

``js
import regx from 'regx';

// RegExp partial to match opening block comment (flags ignored)
const openPartial = /\/\\/i;

// String partial to match closing block comment (extra escaping required)
const closePartial = '\\*\\/';

// Time to write a human-readable expression
const expression = regx('gm')
// Match a non-recursive block comment
(
// Must be first thing on a line
^[\t ]*

${openPartial} // Block opener

// Capture content independently
(
// Match any character including newlines (non-greedy)
[\s\S]*?
)

${closePartial} // Block closer
)

// Grab trailing newlines and discard them
[\r\n]*
;

// The result is the same as if you had written the following
const expression = /(^[\t ]\/\\([\s\S]?)\\/)[\r\n]/gm;
`

API

$3

Creates a template-string tag function. Optionally accepts RegExp [flags][flags].

`js
const a = regx('gm')
^ // start of line
a+ // one or more 'a' characters
$ // end of line
; // result: /^a+$/gm
`

$3

The functions returned by regx() may be cached and reused.

`js
const rx = regx('gm');

const a = rx
^ // start of line
a+ // one or more 'a' characters
$ // end of line
; // result: /^a+$/gm

const b = rx
^ // start of line
b+ // one or more 'b' characters
$ // end of line
; // result: /^b+$/gm
`

All whitespace at the beginning and end of each line is ignored. To match literal whitespace at the beginning or end of a line you must use a character set.

`js
const rx = regx('i');

const spaceBefore = rx
[ ]foo bar
; // result: /[ ]foo bar/i

const spaceAfter = rx
foo bar[ ]
; // result: /foo bar[ ]/i
``

----

© 2016 Shannon Moeller

Licensed under MIT

[guide]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions
[flags]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions#Advanced_searching_with_flags

[amazon-img]: https://img.shields.io/badge/amazon-tip_jar-yellow.svg?style=flat-square
[amazon-url]: https://www.amazon.com/gp/registry/wishlist/1VQM9ID04YPC5?sort=universal-price
[downloads-img]: http://img.shields.io/npm/dm/regx.svg?style=flat-square
[npm-img]: http://img.shields.io/npm/v/regx.svg?style=flat-square
[npm-url]: https://npmjs.org/package/regx