JavaScript implementation of SRL.
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Type Name Latest commit message Commit time
Failed to load latest commit information.


JavaScript implementation of Simple Regex 🎉🎉🎉

npm version Build Status codecov

Because of the JavaScript regex engine, there is something different from Simple Regex

  • Support as to assign capture name with CODE but not regex engine.
  • NOT support if already had/if not already had
  • NO first match and NO all lazy, since in JavaScript lazy means non-greedy (matching the fewest possible characters).


npm install srl


Class SRL accepts a Simple Regex Language string as input, and return the builder for the query.

The builder can agent test/exec method to the generated regex object. Or you can use get() to take the generated regex object.

const SRL = require('srl')
const query = new SRL('letter exactly 3 times')

query.isMatching('aaa') // true
query.getMatch('aaa') // [ 'aaa', index: 0, input: 'aaa' ]

    .get() // /[a-z]{3}[0-9]*$/g

Required Node 6.0+ for the ES6 support, Or you can use Babel to support Node below 6.0.

Using Webpack and babel-loader to pack it if want to use in browsers.


In SRL-JavaScript we apply g flag as default to follow the Simple Regex "standard", so we provide more API to use regex conveniently.

  • isMatching - Validate if the expression matches the given string.

     const query = new SRL('starts with letter twice')
     query.isMatching(' aa') // false
     query.isMatching('bbb') // true
  • getMatch - Get first match of the given string, like run regex.exec once.

    const query = new SRL('capture (letter twice) as word whitespace')
    query.getMatch('aa bb cc dd') // [ 'aa ', 'aa', index: 0, input: 'aa bb cc dd', word: 'aa' ]
  • getMatches - Get all matches of the given string, like a loop to run regex.exec.

    const query = new SRL('capture (letter twice) as word whitespace')
    query.getMatches('aa bb cc dd')
     * [ 
     *     [ 'aa ', 'aa', index: 0, input: 'aa bb cc dd', word: 'aa' ],
     *     [ 'bb ', 'bb', index: 3, input: 'aa bb cc dd', word: 'bb' ],
     *     [ 'cc ', 'cc', index: 6, input: 'aa bb cc dd', word: 'cc' ] 
     * ]
  • removeModifier - Remove specific flag.

     const query = new SRL('capture (letter twice) as word whitespace')
     query.get() // /([a-z]{2})\s/


First, clone repo and init submodule for test.

SRL-JavaScript depends on Mocha and Istanbul to test code. You can use them like this:

npm install

npm test # test 
npm run coverage # Get coverage locally 

How to write Rules, see: Test-Rules.


SRL-JavaScript is published under the MIT license. See LICENSE for more information.