[Haskell-beginners] Still confused
marc.gorenstein at gmail.com
Mon Jul 1 20:42:05 CEST 2013
> Yes. A section is just this conversion of an infix operator to a prefix
function, but with one parameter carried along with it. You can supply it on
either side as appropriate; (/ 8) is the same as (\x -> x / 8) which in turn
is the same as (\x -> (/) x 8), whereas (8 /) is (\x -> 8 / x) is (\x -> (/) 8
x). Note that it must be *inside* the parentheses to be a section; if it's
outside, then it's a normal function (not operator!) parameter.
> brandon s allbery kf8nh sine nomine associates
Hi Brandon (and others),
Thanks very much. I'm no longer confused. I can see that a Section is a
special case that turns a binary infix operator turns into a single-parameter
prefix function. The equivalence to a lambda abstraction makes it clear.
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