[Haskell-cafe] Re: Point-free style

Fritz Ruehr fruehr at willamette.edu
Thu Feb 10 20:29:10 EST 2005

Jerzy pointed out the utility (well, at least the *possibility*) of 
expressions such as the following when writing points-free code (or 
perhaps per Matthew it should be "pointy code" :) ):

	(.) . (.) . (.)

This is the function which composes a 1-argument function with a 
3-argument function (and the pattern generalizes to n in the second 
functional argument). I sometimes itch to use the n=2 case, as in the 
following, but good sense usually gets the better of me:

	(.<) = (.) . (.)

(this allows, for example, concat .< replicate).

One gets the impression of some odd kind of Morse code, or perhaps 
"smileys" / "emoticons" ...

The attached file gives some more detail and examples for the 
points-free fans.

   --  Fritz

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