Don't tell Wil Short about this technology.

July 12, 2013 3:24 PM

Regular Expression Crosswords Do you like regular expressions? Do you like crosswords puzzles? Then you're going to (hate|love) this.
posted by boo_radley (53 comments total)

The person who invented this needs to die.

boo_radley, I will merely wound you for bringing it to my attention.
posted by Tell Me No Lies at 3:37 PM on July 12, 2013 [13 favorites]

For cheating help.
posted by hot_monster at 3:37 PM on July 12, 2013

\.
posted by not_the_water at 3:37 PM on July 12, 2013 [3 favorites]

Oh man. I've had this nightmare. I suck at regex.
posted by eyeballkid at 3:38 PM on July 12, 2013 [1 favorite]

(I|We)(really)?(hate|love)you for posting this(.|!)
posted by Nanukthedog at 3:38 PM on July 12, 2013 [6 favorites]

Although I have to say the "must login with facebook to save" thing truly is evil.
posted by Tell Me No Lies at 3:39 PM on July 12, 2013 [5 favorites]

Tried to nope back out and shit broke my back button. They had me trapped. People who made that site are savages. I was typing in regexes and I don't know what happened. Must have blacked out but now I'm back to serve as a warning.
posted by Ad hominem at 3:43 PM on July 12, 2013 [3 favorites]

``Some people, when confronted with a problem, think "I know, I'll use regular expressions." Now they have two problems.'' - jwz
posted by Blazecock Pileon at 3:44 PM on July 12, 2013 [16 favorites]

It's clever, but will probably be problematic for people who aren't familiar with handling regex. Their "help" button doesn't even explain all the terms used in the tutorial. Good Friday brain food, though!
posted by xedrik at 3:46 PM on July 12, 2013 [1 favorite]

Anyone involved in creating of or popularizing of this will pay. And while I'm enjoying working through these, I've got a nagging feeling that I should be coding up each example in Prolog or passing them to a SAT solver to do all the real work.
posted by benito.strauss at 3:49 PM on July 12, 2013 [2 favorites]

Some people, when confronted with a problem, think "I know, I'll use regular expressions." Now they have two problems. - jwz

One problem across, one problem down.
posted by benito.strauss at 3:50 PM on July 12, 2013 [9 favorites]

Notice! In order to save your progress you have to login with Facebook.

Ugh.
posted by Thorzdad at 3:53 PM on July 12, 2013

Love this, thanks
posted by East Manitoba Regional Junior Kabaddi Champion '94 at 4:31 PM on July 12, 2013

This is the best.
posted by iamkimiam at 4:39 PM on July 12, 2013

oh my gosh yesssss
posted by foxfirefey at 4:41 PM on July 12, 2013

The Microsoft Puzzle Challenge actually had a really great regex puzzle this year. I spent at least an hour on that one alone...
posted by ilikemefi at 4:53 PM on July 12, 2013

I was trying to come up with a complicated regex that is funny.

Then I remembered that there is nothing funny about a complicated regex.
posted by double block and bleed at 4:54 PM on July 12, 2013 [5 favorites]

now you have three problems
posted by thelonius at 5:10 PM on July 12, 2013 [8 favorites]

A hexagonal regex puzzle from the MIT Mystery Hunt.

You're welcome.
posted by spacewrench at 5:12 PM on July 12, 2013 [4 favorites]

Don't tell Will Shortz, either.
posted by Camofrog at 5:14 PM on July 12, 2013 [3 favorites]

Leave Will's shorts out of this, Camofrog.
posted by caution live frogs at 6:15 PM on July 12, 2013

(Intermediate got a lot easier when I realized that like any good crossword, you needn't solve the clue to figure out the answer... So long as the remainder of the puzzle fills in the context for you!)
posted by caution live frogs at 6:17 PM on July 12, 2013 [1 favorite]

"Regex crosswords are a lot like people, Mrs. Simpson. Some of them act badly because they've had a hard life or have been mistreated. But, like people, some of them are just jerks."
posted by mixing at 6:21 PM on July 12, 2013

eyeballkid: "Oh man. I've had this nightmare. I suck at regex."

You and me both.
posted by Samizdata at 6:28 PM on July 12, 2013

At first I was convinced the MIT hexagon puzzle was not solvable by hand, but bit by bit I did it. I think it took me 4 hours. Fun puzzle.
posted by Pruitt-Igoe at 6:44 PM on July 12, 2013

Tip: put .* in every blank and you win every time
posted by mcstayinskool at 8:08 PM on July 12, 2013

How do you put two characters into a cell?
posted by Blazecock Pileon at 8:27 PM on July 12, 2013

Blazecock Pileon: "How do you put two characters into a cell?"

First you write a web browser, then get driven out of business. Then you open a nightclub in San Francisco.
posted by boo_radley at 8:39 PM on July 12, 2013 [11 favorites]

These don't seem that hard. I just finished through "Experienced" after maybe twenty or thirty minutes and it seems like it's less a matter of increasing difficulty than increasing tedium, although the concept is fun.
posted by invitapriore at 8:50 PM on July 12, 2013

How do you put two characters into a cell?

You don't. It confused me a bit at first, but remember that you're doing a crossword style puzzle here. If AB is the answer then A will be in the first cell and B will be in the second.
posted by Tell Me No Lies at 10:05 PM on July 12, 2013

You know, while we're here, I've never understood the old maxim about regular expressions. Like, if you're trying to use them to parse input conforming to a context-free but not regular language, then yes! That is a problem, but it's a pebkac problem, not a regex problem. Otherwise, what easier solution is there for tokenizing? Modeling the DFA that a regular expression maps to is going to require at least as much effort to understand on the part of anyone reading your code, and it's going to take a lot longer to write unless you've got a class or a function that takes a set of states, terminals, transitions, and etc. and spits a DFA out, but then you'd still be reinventing the wheel and slapping an unwieldy interface on it on top of that.
posted by invitapriore at 10:13 PM on July 12, 2013 [2 favorites]

my brain hurts
posted by not_on_display at 10:15 PM on July 12, 2013

As if just one of these things by itself wasn't enough of a frustrating time suck.
posted by nowhere man at 10:20 PM on July 12, 2013

Cute and fun. Not nearly as hard as they seem at first. Thanks for posting.

Orne va zvaq gung vg vf nyfb n pebffjbeq. (Guvf gbb vf n pyhr juvpu vf abg n ertrkc.)

By far the hardest one of the lot is the all symbols one in the 'experienced' section. Even that is solvable without too much hardship once you see what is going on. Also, by far the hardest section is the 'experienced' section. You'll see why.
posted by motty at 10:25 PM on July 12, 2013

Wow, that hexagon thing was tough! Finally finished it, but it took long enough. Thanks, spacewrench!
posted by vasi at 10:37 PM on July 12, 2013

invitapriore: "Otherwise, what easier solution is there for tokenizing?"

IIRC the original jwz complaint was more focused on people who were using regexps inappropriately, eg for parsing markup. If you have a grammar that can be parsed correctly with a regexp, I can't imagine why you wouldn't use one.
posted by vanar sena at 10:39 PM on July 12, 2013 [1 favorite]

You know, while we're here, I've never understood the old maxim about regular expressions. Like, if you're trying to use them to parse input conforming to a context-free but not regular language, then yes! That is a problem, but it's a pebkac problem, not a regex problem. Otherwise, what easier solution is there for tokenizing?

I've always taken that maxim to mean that if you get involved with regular expressions it is going to be a pain in the ass. That doesn't mean it isn't the right way to do it, just that it's going to be painful.
posted by Tell Me No Lies at 11:05 PM on July 12, 2013 [1 favorite]

motty: "Cute and fun. Not nearly as hard as they seem at first. Thanks for posting.

Orne va zvaq gung vg vf nyfb n pebffjbeq. (Guvf gbb vf n pyhr juvpu vf abg n ertrkc.)

By far the hardest one of the lot is the all symbols one in the 'experienced' section. Even that is solvable without too much hardship once you see what is going on. Also, by far the hardest section is the 'experienced' section. You'll see why."

Whfg n gvc - V vafgnyyrq n EBG13 obbxznexyrg fcrpvsvpnyyl sbe ZrgnSvygre. Arire hfrq vg zhpu orsber gura. V nz zber bs n EBG104 sna zlfrys.
posted by Samizdata at 11:15 PM on July 12, 2013

Somehow this thread led me to agrep - which is very useful and didn't know existed. It allows for fuzzy matching eg.

agrep -2 Laszlo

László
Lászlo
Laszlo

The first László is the correct spelling but it might be anglicized and will match those too. The -2 says allow for up to 2 errors so it would match many possible variations and misspellings, though could also mismatch, thus fuzzy, but still useful when dealing with natural language.
posted by stbalbach at 11:51 PM on July 12, 2013 [2 favorites]

FYI, jwz was not really the author of the "two problems" line, he just generalized an existing sig line joke by substituting "regular expressions" for "awk".
posted by Rhomboid at 12:27 AM on July 13, 2013 [2 favorites]

The regex-specific version goes like this: "... and now you have + problems."
posted by seanmpuckett at 4:10 AM on July 13, 2013 [1 favorite]

How do you put two characters into a cell?

You have to write a regular expression
posted by mcstayinskool at 5:17 AM on July 13, 2013

I have almost no coding experience (as in, I've learned a bit of html and nothing else) and after a brief regex tutorial, I was able to do these all pretty quickly. Except the all-symbol ones.
posted by outlandishmarxist at 5:20 AM on July 13, 2013

That was fun! My biggest problem with the all-symbols one was reading them sideways.
posted by grouse at 7:59 AM on July 13, 2013

Url, gur chmmyr gvgyr (fbzrgvzrf?) tvirf lbh na rkgen pyhr!
posted by spacewrench at 8:00 AM on July 13, 2013

.*

I win.
posted by yerfatma at 8:36 AM on July 13, 2013

Otherwise, what easier solution is there for tokenizing?

Parser combinators.

The first "experienced" one is quite easy.
posted by kenko at 8:53 AM on July 13, 2013

Even the all-symbols "experienced" one is easy, especially once you discern the pattern.
posted by kenko at 9:46 AM on July 13, 2013

This is really fun and actually not that hard. (I have the last experienced one left, and also all the double cross ones.)

Once I get to a printer, I'm trying the hexagonal one.
posted by jeather at 7:42 PM on July 14, 2013

If, one day, while out exploring the universe humanity meets an alien civilization that communicates exclusively through Regular Expressions, then I would be, in that one and only one scenario, completely fine with genocide.
posted by blue_beetle at 2:51 PM on July 19, 2013

Maybe I have to get farther to hate this, but so far it's the best thing ever.
posted by DU at 10:02 AM on July 31, 2013

Maybe I spoke too soon. WTF is "/+"? Except that some parsers use / as a delimiter, it isn't special, so "/" should match. And yet it doesn't.
posted by DU at 10:17 AM on July 31, 2013

NM, I'm an idiot.
posted by DU at 10:21 AM on July 31, 2013 [1 favorite]