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digitalmars.D.bugs - [Issue 13029] New: cumulate for std.algorithm


          Issue ID: 13029
           Summary: cumulate for std.algorithm
           Product: D
           Version: D2
          Hardware: x86_64
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: Phobos
          Assignee: nobody puremagic.com
          Reporter: jens.k.mueller gmx.de

cumulate is an algorithm that I use rarely but still I believe it belongs into
the standard library.
cumulate applies a binary function to a range in a cumulative manner. Matlab
has cumsum and cumprod (see
http://www.mathworks.de/de/help/matlab/ref/cumsum.html and

Some unittests to define its behavior.

   assert([].cumulate!((a,b) => a + b).equal([]));
   assert([1].cumulate!((a,b) => a + b).equal([1]));
   assert([1,2,3].cumulate!((a,b) => a + b).equal([1,3,6]));

It may very well be the case that one can express this functionality using
other functions from std.algorithm. If there is an easy approach, I may follow
that way. I couldn't fine one.

Jul 03 2014