Proposal: Performance improvements for Data.IntMap

[Ian Lynagh]

On Tue, Aug 31, 2010 at 03:09:34AM -0700, Donald Bruce Stewart wrote:
> 
> #4279: Proposal: Performance improvements for Data.IntMap
> http://hackage.haskell.org/trac/ghc/ticket/4279

Same .Internals comment as for Data.Map in #4277.

> -        | zero k m      -> let (found,l') = insertLookupWithKey f k x l in (found,Bin p m l' r)
> -        | otherwise     -> let (found,r') = insertLookupWithKey f k x r in (found,Bin p m l r')
> +        | zero k m      = case go l of (found, l') -> (found,Bin p m l' r)
> +        | otherwise     = case go r of (found, r') -> (found,Bin p m l r')

I noticed you didn't convert the let's to case's in Data.Map, in both
insertLookupWithKey and insertLookupWithKey'. Why did you convert them
in IntMap's insertLookupWithKey but not Map?

Likewise updateLookupWithKey.


Unrelated to your changes, but I think it would be worth renaming
foldr' (an internal helper) to avoid confusion.


Thanks
Ian