generating permutations

[mfulton26]

Would you be open to the addition of a generator function to generate all permutations of an array?

e.g. I have one I ported from Collections2.java · google/guava that I could contribute. It is an implementation of the Plain Changes algorithm for permutations generation described in Knuth's "The Art of Computer Programming", Volume 4, Chapter 7, Section 7.2.1.2.

[curran]

That sounds cool.