Enjoy, sickos
Credit: Dan Gulotta, based on an idea by Palmer Mebane (Mystery Hunt 2013) https://devjoe.appspot.com/huntindex/puzzle/mit2013601
(link includes an answer key! Thanks to @zarfeblong for linking the original author)
MIT Mystery Hunt Puzzle Index: Puzzle Data

@refreshingapathy thats impressive and disgusting at the same time
@refreshingapathy oh I'm /S|MM|HHH/, alright

@refreshingapathy

I am equally horrified and excited.

@refreshingapathy

Spare my poor aging but obsessive brain, these aren't real dictionary words, correct? I'm trying to make sure I'm not misunderstanding the regexes but I can't think of or find many words with "CCC" or "RHH" in them? (I mean with or without regexes, making an open hex crossword with real words would be a ridiculously impressive accomplishment. . .)

@MichaelTBacon I solved a few squares last night before my eyes went completely crossed and none of my solutions were dictionary words
@MichaelTBacon @refreshingapathy these are not dictionary words. One of the clues is [CR]*, basically a string of C and R with no vowels
@Aubrey @MichaelTBacon that’s correct - the solutions are not dictionary words. I posted the answer key as a reply to the original if you want to check your work.
Regex Crossword

A crossword puzzle game using regular expressions. Earn achievements completing puzzle challenges. Easy tutorials for people new to regular expressions.

Regex Crossword
@tdelmas I only played the tutorial and I'm already sad.

@refreshingapathy @chrisamaphone Credit: Dan Gulotta, based on an idea by Palmer Mebane
(Mystery Hunt 2013)

https://devjoe.appspot.com/huntindex/puzzle/mit2013601

MIT Mystery Hunt Puzzle Index: Puzzle Data

@zarfeblong @chrisamaphone THANK YOU - been trying to find the answer key this morning and couldn’t!
@refreshingapathy Wait a second. Has this been designed to have a solution or is it a random joke?
The field at the bottom left is covered by `.` from all three directions.
@henryk it is real and has real solutions (though not dictionary words) - @zarfeblong was kind enough to link to the original creator's site https://devjoe.appspot.com/huntindex/puzzle/mit2013601
MIT Mystery Hunt Puzzle Index: Puzzle Data

@refreshingapathy @zarfeblong
I'm impressed. I wrote some code to solve it and it both does have a unique solution and at the same time doesn't appear to be overspecified, e.g. all the regexes are necessary.
@henryk @refreshingapathy MIT Puzzle Hunt has very well-developed design practice of paying attention to stuff like that!
@henryk @refreshingapathy @zarfeblong I'm wondering if the regexes have to cover the whole lines? Like on the top row, if I understand correctly, I have to place 2 H. If regex cover the full lines, only cells 2 and 7 can be an H but cell 2 can also only be C or M? But if regexes don't have to cover the whole line, why put stuff like the second row which is equivalent to .* or not use .? ?
@henryk @refreshingapathy @zarfeblong hmmm, my regexes skill might be rusty, I went with ^ inside [...] means start of line but that's not it "^^
@gkrnours Yes, regexea are implicitly anchored at start and end. BUT: .* means "anything", so it can be length 0, and it also can also include H. So the top line is "at least two H, anywhere".
@refreshingapathy
Is this a fresh one? I know I did one of these in the past couple of years, maybe at Mystery Hunt or in some other puzzle hunt.
@epw
@smolwaffle not a fresh one, its from the Mystery Hunt
@refreshingapathy iirc my company internal repos have a solver for these somewhere, because we have enough of That Type of Nerd.
@swift whatever coworkers wrote that has my respect, admiration, and pity all at once
@refreshingapathy they didn't choose the puzzle life, the puzzle life chose them

@refreshingapathy I have to block this before either a) solving it manually, or b) writing a recursive descent reverse regex string generator and applying it to compute a solution.

Spoiler: I'm more likely to try option b first.

@alan the solution to regex is... more regex!

@refreshingapathy Well, yeah. What else? I mean seriously, half my career to date has revolved around regexes... including a regex library I wrote decades ago when no parser was available for the language I was working in (Pascal, IIRC).

Then I used that to parse FORTRAN programs and extract documentation and generate cross-references for variables.

Oh god, I am old. 😂

@alan @refreshingapathy
there are not many people whoms last word will be "regex" 😬 😂
@alan @refreshingapathy I had a little fun a few years ago writing lo-res Fortran source code visualizers: draw a bitmap that shows the shape of code and color-codes statements, line labels, continuation marks, comments, and stray marks past column 72. A different one to convert GOTO logic to a Graphviz digraph. I was curious what you could learn by looking only at shape and structure without the text. F66, F77, and F90 have very distinct patterns.
@refreshingapathy when I see something like this, my first inclination is not to done it by hand, but to write a program that would solve it 🤷🏼‍♂️
@dodecahedron this sounds like something you might enjoy :D
@refreshingapathy there was an app on F-droid for Regex crosswords too and I still dont understand how to even start xD

@refreshingapathy that’s great, thanks!

At the first glance it seems that the bottom-left corner gives it a good spin.

@refreshingapathy the easy solution is to write an algo to generate these kinds of torture devices 🤣
@refreshingapathy @kimvanwyk Had a lot of fun completing this one 10+ years ago (I forget exactly when). Yes, I am a regex geek, why do you ask? LOL.
@leoncowle @refreshingapathy good to know, thanks. I too am a regex geek ( presumably not what most people mean when they declare themselves a regular guy) so I'm looking forward to do this one.
@refreshingapathy done it! That was a LOT of fun. I may be a sicko.
@refreshingapathy is there an answer sheet to compare to mine, by any chance?