Yet another run at reduce (original) (raw)

Doug Lea dl at cs.oswego.edu
Tue Jan 8 06:59:14 PST 2013

On 01/07/13 20:31, Brian Goetz wrote:

The requirement for B is that: - your combining functions are associative and commutative

We will someday need to put out a clear story about this here and elsewhere: The requirement is that you do not care about order. Which may arise because source is unordered, destination is unordered, the op is commutative, or just because you just don't care. For example, collecting/merging elements using list-concat may be fine to do this way if you need a List but don't care about the order of elements in that list.

-Doug

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