[jgalt212]

Definitely a debugable way to write regexes. Whenever I have to maintain a hairy regex, I like to plot the regex as a railroad diagram.

These web based tools can do it:

https://www.debuggex.com/

http://jex.im/regulex/

[philjohn]

Love it - just visualised the PCRE generated from the EBNF for the N-Triples RDF serialisation format[1] :)

https://www.debuggex.com/r/Yxqws81Uif-BGBN8

Important note - this is built up programmatically, it's not just a string dumped in a parser!

[1] http://www.w3.org/TR/n-triples/#n-triples-grammar

[jgalt212]

That is one hairy regex. Now the inverse would be even better. You modify the railroad chart and the regex updates.

[philjohn]

Fairly hairy, yes, but if you follow the railroad tracks, it's quite succint for what it's doing!