... the readability of reduce on non-associative arguments ...
ASIDE:
Dijkstra, "It is all distributivity"
http://www.cs.utexas.edu/~EWD/transcriptions/EWD11xx/EWD1142.html
To begin with we observe —with apologies for the two different
usages of parentheses—
(x•z)•y = x•(z•y)
= {definition of derived operators}
(•y).((x•).z) = (x•).((•y).z)
= {definition of functional composition}
((•y)◦(x•)).z = ((x•)◦(•y)).z ,
hence, that a binary operator is "associative" means that its
derived unary operators commute.
End of Aside
-Dave
is it just me, or does ((•y)◦(x•)).z resemble a (Huet) zipper?
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