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Re:Why Haskell is beyond ready for Prime Time by time_management on Thursday January 15, 2009 @08:37AM (#435120)
Have you had this problem with Haskell?

I've heard that Haskell's space performance isn't great, but I don't know enough about the language to confirm or deny this.

I would recommend, if you're concerned with performance, using Ocaml. You can compile it down to native code, and its performance characteristics are comparable to C.

Re:Why Haskell is beyond ready for Prime Time by brl on Thursday January 15, 2009 @12:05PM (#435326)
Yes, I have had to solve this problem a lot. It's probably my own fault because I am an inexperienced Haskell programmer, and maybe it's just because I'm incompetent but I find space performance very difficult to reason about.

It seems like anybody can make these mistakes, and they are mostly invisible until one day your problem size is a little bit larger than normal and your program explodes and crashes.

Re:Why Haskell is beyond ready for Prime Time by time_management on Thursday January 15, 2009 @12:51PM (#435408)
Noob question: Why is space performance so opaque in a lazy language?
Re:Why Haskell is beyond ready for Prime Time by brl on Thursday January 15, 2009 @02:38PM (#435568)
Noob answer:

In a strict language, you write an expression and it's perfectly clear when it will be evaluated.

With lazy evaluation to know if or when an expression will be evaluated you have to follow it through possibly many layers of function calls (which may have been written by somebody else) looking for a place where it needs to be evaluated. Along the way it may become embedded in other expressions which complicates the problem.

How do you know when an expression needs to be evaluated? I don't know if I'm smart enough to understand the answer to that question:

http://en.wikibooks.org/wiki/Haskell/Denotational_semantics#...