Convert Regular Expressions into text, for testing

1.0.0 2021-11-14 08:09 UTC

This package is auto-updated.

Last update: 2024-04-14 17:46:17 UTC


Build Status

Use Regular Expressions to generate strings.


This library is installed via Composer. To install, use composer require pointybeard/reverse-regex in your application.




use ReverseRegex\Lexer;
use ReverseRegex\Random\SimpleRandom;
use ReverseRegex\Parser;
use ReverseRegex\Generator\Scope;

require "vendor/autoload.php";

$pattern = "[a-z0-9]{10}"; // 10 random letters and numbers

$lexer = new Lexer($pattern);
$random = new SimpleRandom();
$parser = new Parser($lexer, new Scope(), new Scope());
$generator = $parser->parse()->getResult();

$result = '';

$parser = new Parser($lexer,new Scope(),new Scope());

var_dump($generator->generate($result, $random));
// string(10) "j2ydisgoks"

See https://github.com/pointybeard-forks/ReverseRegex/tree/master/examples for more examples.

Notes When Writing Regular Expressions

  1. Escape all meta-characters i.e. if you need to escape the character in a regex you will need to escape here.
  2. Not all meta-characters are suppported see list below.
  3. Use \X{####} to specify unicode value use [\X{####}-\X{####}] to specify range.
  4. Unicdoe \p not supported, I could not find a port of UCD to php, maybe in the future support be added.
  5. Quantifiers are applied to left most group, literal or character class.
  6. Beware of the + and * quantifers they apply a possible maxium number of occurances up to PHP_INT_MAX.

Supported Syntax

Example Description Resulting String
(abcf) Support literals this would generate string 'abcf'
\((abcf)\) Escape meta characters as you normally would in a regex '(abcf)'
[a-z] Character Classes are supported 'a'
a{5} Quantifiers supported always last group or literal or character class 'aaaaa'
a{1,5} Range Quantifiers supported 'aa'
a|b|c Alternation supported pick one of three at random 'b'
a|(y|d){5} Groups supported with alternation and quantifiers 'ddddd', 'a', or 'yyyyy'
\d Digit shorthand equ [0-9] '1'
\w word character shorthand equ [a-zA-Z0-9_] 'j'
\W Non word character shorthand equ [^a-zA-Z0-9_] 'j'
\s White space shorthand ASCII only ' '
\S Non White space shorthand ASCII only 'i'
. Dot all ASCII characters '$'
* + ? Short hand quantifiers, recommend not use them
\X{00FF}[\X{00FF}-\X{00FF}] Unicode ranges
\xFF[\xFF-\xFF] Hex ranges



  • This library works with PHP 7.2 or above.


If you believe you have found a bug, please report it using the GitHub issue tracker.



"ReverseRegex" is released under the MIT License. See LICENCE for details.