This asset has only been tested with GameMaker: Studio 1.
Download demo: http://www.mediafire.com/download/f2yknhxm7049xbt/GML+Regular+Expressions.exe
Forum thread: https://forum.yoyogames.com/index.php?threads/gml-regular-expressions-free.3290/
With this asset you can create and compile regular expressions to nondeterministic finite state automata and check if strings match them. It's all written in GML, so it's easy to export to multiple platforms. It's not as vast in functionality as regex, but still very useful.
Remember to read the asset's EULA:
End User Licence Agreement (EULA).