[Haskell-beginners] Factorials using foldx

[Paul Johnston]

Hi (First question so be gentle)!
Just started to look at Haskell and I was wondering about various versions of calculating factorials.

If I have 

facr 0 = 1
facr n = foldr (*) 1 [1..n]

facl 0 = 1
facl n = foldl (*) 1 [1..n]

Is there any difference in efficiency, I remember reading it is better to count down than to count up but left to right or right to left :-)

Cheers Paul

Paul Johnston
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Unix 
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            %rm* .o
            rm:.o no such file or directory