Re: modeling out of memory

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Greetings,

1) How does one model "out of memory" condition in Haskell, perhaps using a Maybe type?

Unfortuntely not since it would not be referentially transparent. It's part of a more general issue of exceptions in pure code.

You can't have

calculateSomething :: X -> Maybe Y

Such that it returns Nothing if it ran out of memory.

<snip>

Probably the thing to do is just catch the exceptions rather than have your functions return Maybe types. That way you don't have to deal with Maybes all over the place.

Does this make the use of Monads doubtful? I mean it doesn't seem easy to have a completely pure language, and the time one starts introducing few impurities one also starts thinking why not include many others? Just a thought...