Allow recur in functions

[fasterthanlime]

Not only in loop.

---

Also:

Cljs code

(loop [i 0
       j 0]
  (when (< i 10)
    (prn "i = " i)
    (recur (inc i) j)))

Shin output

(function () {
  var $$__i1 = 0;
  var $$__j2 = 0;
  var recur = null;
  var $$__loopret3 = null;
  while (true) {
    if ($s.call(null, $$__i1, 10)) {
      prn.call(null, 'i = ', $$__i1);
      $$__loopret3 = recur = [
  inc.call(null, $$__i1),
$$__j2
  ];
    } else {
    }
    if (recur) {
      $$__i1 = recur[0];
      $$__j2 = recur[1];
      recur = null;
      continue;
    } else {
    }
    break;
  }
  return $$__loopret3;
}());

Reference output

var i_7994 = 0;
var j_7995 = 0;
while (true) {
    if ((i_7994 < 10)) {
        cljs.core.prn.call(null, "i = ", i_7994); {
            var G__7996 = (i_7994 + 1);
            var G__7997 = j_7995;
            i_7994 = G__7996;
            j_7995 = G__7997;
            continue;
        }
    } else {}
    break;
}

---

So we can do better. Much better.