[Haskell-cafe] On the various faces of Composition

Jacques Carette carette at mcmaster.ca
Tue Dec 19 12:52:24 EST 2006

[As recently seen on LtU - http://lambda-the-ultimate.org/node/1919] An 
amazing paper
on "composition" as seen from APL and J.  The terminology (using verbs, 
nouns, adverbs, etc) is _so_ much more evocative than the terminology 
used for similar ideas here, I hope that some of it can rub off.  Also, 
if anyone thought that "point free" programming was something 
mostly-recent, mostly-Haskell, they _really_ need to read this paper!

Also, I am fairly sure that some of the high-powered operators in J may 
stress Haskell's type system quite severely, if not to the breaking 
point.  It would be a fascinating exercise to try to reproduce the 
various examples in that paper in as-idiomatic-as-possible Haskell.

While J's syntax is somewhat on the terse side, its power regarding 
practical mathematics is superb -- especially when it comes to 


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