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Comment by derefr | Hacker News Reader

They're important in CS theory, sure, but you sure don't want to encounter one in raw form lurking in a regular codebase. (Just like you wouldn't want to encounter monadic IO in raw >>= form.)

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Using the y combinator outside of some ridiculously abstract code would be irritating. Using (>>=) makes sense sometimes though. For instance if you just wanted to echo something you could do

  do stuff <- getLine
     putStrLn stuff

but the stuff variable is then unnecessarily introduced. You could instead just write

  getLine >>= putStrLn

or the flipped version if you want it to read more like function application

  putStrLn =<< getLine

how do neither of you get the obvious joke OP is making with "I think there's definitely a rule against dismissing Y combinators on news.ycombinator.com". (he's making a joke out of the fact that YCombinator is named after the construct.)

That wasn't a joke.. People have been hellbanned for speaking ill of Y combinators.

Really?

Maybe that was the joke.

>Just like you wouldn't want to encounter monadic IO in raw >>= form

Yes I would. I would much rather see "getLine >>= putStrLn" than a 2 line do block.

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