argument ordering (was: Re: Priority Queues, or lack thereof)
Malcolm Wallace
Malcolm.Wallace at cs.york.ac.uk
Fri Aug 19 10:43:16 EDT 2005
> This style supports multiple operations nicely, especially with combined
> with the $ operator.
But note that the version with $ is actually longer than the one
with nested parens! And where the operands are not statically known,
the different orderings do simply come down to foldl/foldr preference:
> insert 1 $ insert 2 $ insert 3 $ someSet
== foldr insert someSet [1,2,3]
> insert (insert (insert someSet 3) 2) 1
== foldl insert someSet [3,2,1]
In some sense the foldl variant is more 'obvious' about the order in
which elements are actually inserted.
Regards,
Malcolm
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