Support "sets" of results, as in One Roll Engine

[puk3]

Organize dice by matching numbers, and count sets of each.

Example:

rolling 10d10 and counting sets may produce something similar to:

7, 7, 7
5, 5
3, 3
9
4
2

Reference: http://arcdream.com/home/2011/04/a-one-roll-engine-tutorial/