[parenscript-devel] Why is there a WITH clause in my loop?

Here's a really strange one.

We have a form like the following. I've stripped it down for brevity, so it looks weird:

(loop :for time :from time1 :below time2 :do (when (foo (λ () (bar (λ () (blah)) time)) time) (break)))

It used to generate this:

for (var time = time1; time < time2; time += 1) { if (foo(function () { return barr(function () { return blah(); }, time); }, time)) { break; }; };

But now it generates this:

for (var time = time1; time < time2; time += 1) { with ({ time : time }) { if (foo(function () { return bar(function () { return blah(); }, time); }, time)) { break; }; }; };

That is one weird WITH clause in there! No doubt it has something to do with lexical scoping magic going on under the hood. But I definitely don't want it in a performance-critical loop.

Daniel