regex-not

What is regex-not?

The regex-not npm package is designed to create regular expressions for matching everything except a specified pattern. This can be particularly useful when you need to exclude certain patterns from your matches.

What are regex-not's main functionalities?

Basic Negation

This feature allows you to create a regular expression that matches any string except the specified pattern. In this example, the pattern 'foo' is excluded from the matches.

const not = require('regex-not');
const re = not('foo');
console.log(re); // => /^(?:(?!^(?:foo)$).)+$/

Negation with Flags

This feature allows you to add flags to the negated regular expression. In this example, the global flag 'g' is added to the pattern that excludes 'foo'.

const not = require('regex-not');
const re = not('foo', { flags: 'g' });
console.log(re); // => /^(?:(?!^(?:foo)$).)+$/g

Negation with Custom Delimiters

This feature allows you to specify custom delimiters for the negated pattern. In this example, the delimiters '<' and '>' are used around the pattern 'foo'.

const not = require('regex-not');
const re = not('foo', { delimiters: ['<', '>'] });
console.log(re); // => /^(?:(?!<foo>).)+$/

Other packages similar to regex-not

negate

The 'negate' package provides similar functionality by allowing you to create a negated version of a given regular expression. It is simpler and more focused on negation without additional customization options like flags or delimiters.

README

regex-not

Create a javascript regular expression for matching everything except for the given string.

Install

Install with npm:

$ npm install --save regex-not

Usage

var not = require('regex-not');

The main export is a function that takes a string an options object.

not(string[, options]);

Example

var not = require('regex-not');
console.log(not('foo'));
//=> /^(?:(?!^(?:foo)$).)*$/

Strict matching

By default, the returned regex is for strictly (not) matching the exact given pattern (in other words, "match this string if it does NOT exactly equal foo"):

var re = not('foo');
console.log(re.test('foo'));     //=> false
console.log(re.test('bar'));     //=> true
console.log(re.test('foobar'));  //=> true
console.log(re.test('barfoo'));  //=> true

.create

Get a string, so you can create your own regex:

console.log(not.create('foo'));
//=> '(?:(?!^(?:foo)$).)*'

Options

options.contains

You can relax strict matching by setting options.contains to true (in other words, "match this string if it does NOT contain foo"):

var re = not('foo');
console.log(re.test('foo', {contains: true}));     //=> false
console.log(re.test('bar', {contains: true}));     //=> true
console.log(re.test('foobar', {contains: true}));  //=> false
console.log(re.test('barfoo', {contains: true}));  //=> false

About

Related projects

• regex-cache: Memoize the results of a call to the RegExp constructor, avoiding repetitious runtime compilation of… more | homepage
• to-regex: Generate a regex from a string or array of strings. | homepage

Contributing

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.

Building docs

(This document was generated by verb-generate-readme (a verb generator), please don't edit the readme directly. Any changes to the readme must be made in .verb.md.)

To generate the readme and API documentation with verb:

$ npm install -g verb verb-generate-readme && verb

Running tests

Install dev dependencies:

$ npm install -d && npm test

Author

Jon Schlinkert

• github/jonschlinkert
• twitter/jonschlinkert

License

Copyright © 2016, Jon Schlinkert. Released under the MIT license.

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This file was generated by verb-generate-readme, v0.1.31, on September 26, 2016.