From: "Kontra, Gergely" <kgergely@...>
Date: 2002-06-06T23:55:00+09:00
Subject: Array.foldr (Array.reduce)

Hi!

I've noticed ruby has nice high level functions.
But I cannot find the reduce or foldr method.

I've discovered the inject method in the Ruby book.
It is very similar to one of the fold(l/r) methods in SML.

The def of foldr is:
where
+ denotes any kind of operator with 2 operands
e is the (right) unit element 

folr e + array = array1 + (array2 + ... + (arrayn + e)...)

And foldl is the other way (if + is associative, then it gives the same
result)

If inject will be available, will foldl and foldr (=reduce) also?
Thanks in advance.

Gergo

+-[Kontra, Gergely @ Budapest University of Technology and Economics]-+
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