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0 pointskarma_vaccum1239y ago0 comments

Haskell's runtime has one overriding attribute: laziness. If laziness is not desirable in your domain, Haskell is not a useful option

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knucklesandwich9y ago

FWIW, strictness may be introduced into haskell programs. Weak-head normal-form evaluation is builtin with the "seq" function and the "deepseq" library is commonly used for fully normal form evaluation of expressions.

GHC 8 also introduces the Strict and StrictData pragmas[1] which allow you to make a module (or its types) fully strictly evaluated.

[1]: https://ghc.haskell.org/trac/ghc/wiki/StrictPragma

tinco9y ago

Can you give me an example of a domain where laziness is not desirable? I only do Haskell for side projects, so perhaps I lack exposure to some domains.

Terribledactyl9y ago

Laziness can make it hard or counterintuitive to determine the runtime properties of your program, especially with regards to memory. Same with real-time systems. But you can turn it off, or force evaluation if needed.

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