I just ran into a strange bug where the gensym'd suffixes on loop control variables change to the wrong thing. The bug appears to be triggered by a (RETURN) form inside a loop that has more than one FOR clause. For each extra clause, the suffixes increase by one. I haven't tried to track down the cause of the bug, but I did just push a failing test (LOOP-PARALLEL-CLAUSES-WITH-RETURN) to illustrate it.
(defun-js foo () (loop :for i :from 0 :below 10 :for x = (* i 10) :when (> i 5) :do (return x) :collect i))
=> (note added comments below):
function foo() { return (function () { var collect3170 = []; var loopResultVarSet3171 = null; var loopResultVar3172 = null; for (var i = 0; i < 10; i += 1) { var x3171 = i * 10; if (i > 5) { loopResultVarSet3172 = true; // <---- suffix should be 3171, not 3172 loopResultVar3173 = x3171; // <---- suffix should be 3172, not 3173 break; }; collect3170.push(i); }; if (loopResultVarSet3171) { return loopResultVar3172; }; return collect3170; })(); };
Daniel