Re: [Haskell-beginners] Important coding guideline and library proposal

... or just say that it's O(n) in the docs. And if n is infinity you'll be waiting for a while. (Sorry Stephen... meant that for the list) On Sun, Nov 22, 2009 at 2:33 PM, Stephen Tetley wrote:

Hi Daniel

Hmm, maybe the docs in Data.List should say that length is recursively calculated. I know you can view the source from Haddock, and its also obvious once you think of list as being defined by an algebriac type, but lists in other languages (read OO) often have track length as part of the ADT making it constant time to get hold of.

Best wishes

Stephen

2009/11/22 Daniel Fischer :

...

Guideline:

NEVER, *never ever*, use 'length' ***unless you really want to know the exact length of a list***

Proposal: rename 'length' to 'yesIReallyWantToKnowTheExactLengthOfThisListSoPleaseCalculateItForMe' to reduce performance bugs caused by naive uses of length. _______________________________________________ Beginners mailing list Beginners@haskell.org http://www.haskell.org/mailman/listinfo/beginners

_______________________________________________ Beginners mailing list Beginners@haskell.org http://www.haskell.org/mailman/listinfo/beginners

-- keithsheppard.name