As it’s not that much lines of code, I decided to do a port for PHP – et voila:

https://github.com/gherkins/regexpbuilderphp

This is basically regex with PHP the easy way:

Say you want to validate some currency string like “€ 105,99” but want “€ 12.000,95” to be also valid.
Coming up with a regex for that i would find challenging, to say the least.

PHP RegExpBuilder to the rescue:

(you can simply install it via composer)

composer require gherkins/regexpbuilderphp:dev-master

Then you’ll be able to do:

$builder = new \Gherkins\RegExpBuilderPHP\RegExpBuilder();


    $builder1 = $builder
        ->find("€")
        ->exactly(1)->whitespace()
        ->min(1)->digits()
        ->then(",")
        ->digit()
        ->digit();
        
    //builder 1 will take care of the cases without a thousand-seperator

    $builder1->getRegExp()->test("€ 128,99");     //true
    $builder1->getRegExp()->test("€ 81,99");      //true
        
       
                     
    $builder2 = $builder->getNew()
        ->find("€")
        ->exactly(1)->whitespace()
        ->min(1)->digits()
        ->then(".")
        ->exactly(3)->digits()
        ->then(",")
        ->digit()
        ->digit();
        
    //builder 1 will take care of the cases *with* the thousand-seperator

    $builder2->getRegExp()->test("€ 1.228,99");   //true
    $builder2->getRegExp()->test("€ 452.000,99"); //true
        
        
    //you can then combine both builders to get a regex which handles all cases:
       
    $combined = $this->r->getNew()
        ->either($builder1)
        ->orLike($builder2);
        
    $combined->getRegExp()->test("€ 128,99");     //true
    $combined->getRegExp()->test("€ 81,99");      //true
    $combined->getRegExp()->test("€ 1.228,99");   //true
    $combined->getRegExp()->test("€ 452.000,99"); //true

This might be a bit verbose if you don’t have any problem with:

(?:(?:(?:(?:€){1,1})(?:(?:\s){1,1})(?:(?:(?:\d)){1,})(?:(?:,){1,1})(?:\d)(?:\d))|(?:(?:(?:€){1,1})(?:(?:\s){1,1})(?:(?:(?:\d)){1,})(?:(?:\.){1,1})(?:(?:(?:\d)){3,3})(?:(?:,){1,1})(?:\d)(?:\d)))

..but I really do like it ;)

https://github.com/gherkins/regexpbuilderphp