A while back I remember someone tried to write an alternative R implementation.

Can you call R from Julia yet? You can do it from Python, but converting between R and Python data structures can be painful. I imagine it would be less so with Julia being "more vectorized" than Python.

There's also the issue that vectorized operations tend to be very _fast_ but algorithmically inefficient. Even if expressions are evaluated lazily, there is no compiler to recognize that computing the value of

    any(is.na(x))

can short-circuit as soon as a single NA value is found. Instead all of `is.na(x)` is computed first, and then `any()` is computed on the result.

I imagine this a problem in any non-compiled (ahead-of-time or just-in-time) language. Wondering what your thoughts were, since it seems like a related issue.