Add comparison to other languages and standard libraries

[domenic]

I think a valuable part of a proposal like this is to compare with how other languages and standard libraries have solved this issue. I'd be curious to see C# Enumerables, Java streams, Ruby, and Python at least.

[leebyron]

Excellent feedback. I'll do some research.

[kaleb]

python has the reversed function which returns a reverse_iterator. The reversed function can either take an object that has a __reversed__ method (analog to Symbol.reverseIterator) or an object that meets the "sequence protocol", e.g. in JavaScript it would have a numeric length property.