sum_int64


Description:


public Collector<int64?,Object,G> sum_int64<G> (owned MapFunc<int64?,G> mapper)

Returns a collector that produces the sum of the given function applied to the elements. If there are no elements, the result is 0.

The mapper function must not return null.

The arithmetic wraps around on overflow; e.g. the sum of int64.MAX and 1 => int64.MIN

Parameters:

mapper

a mapping function

Returns:

the collector implementation


Namespace: Gpseq.Collectors
Package: gpseq-1.0