[ufo]

Do you think the performance is really going to be that bad in the regular Lua interpreter? I wonder if its going to be better or worse than the underscore.lua approach of using arrays instead of iterators.

Also, are you using lots of 5.1 specific stuff (setfenv, ...) or would this also be easily ported to 5.2?

[rtsisyk]

The library code is Lua 5.1 compatible (except bitwise functions in "operator" submodule, but it can be easily replaced with "bit32" or even removed).

Some high-order functions heavily use recursion just to support multireturn iterators (yes, you can use multireturn with map, reduce, filter and so on). I plan to benchmark these parts and add optimized versions for non-JIT Lua if necessary.

I will try to make a patch in the next couple of days. Thanks for your interest!