Regexes are D&D magic-user spells.
You need at a least an hour to compose one.
You're going to want a full night's sleep (and preferably a fresh cup of coffee) before you even think about tackling that task.
The moment you finish typing one out, it is impossible to decipher what it does or how it does it.
Even copying and pasting one is a task fraught with arcane peril.
And, I mean, can you think of a more D&D-sounding phrase than "Regexian Magic"?
Of course not. There isn't one.