satyr 4e39e2e -- efficient closures in loops -- pulling them out.

lib/nodes.js

@@ -1600,6 +1600,9 @@
       if (namePart) {
         varPart = idt + namePart + ';\n';
       }
+      if (!this.pattern) {
+        defPart += this.pluckDirectCall(o, body, name, index);
+      }
       code = guardPart + varPart;
       if (!body.isEmpty()) {
         if (o.level > LEVEL_TOP || this.returns) {
@@ -1619,6 +1622,40 @@
       }
       return defPart + this.tab + ("for (" + forPart + ") {" + code + "}") + retPart;
     };
+    For.prototype.pluckDirectCall = function(o, body, name, index) {
+      var arg, args, base, defs, expr, fn, i, idx, ref, val, _len, _len2, _ref, _ref2, _ref3;
+      defs = '';
+      _ref = body.expressions;
+      for (idx = 0, _len = _ref.length; idx < _len; idx++) {
+        expr = _ref[idx];
+        expr = expr.unwrapAll();
+        if (!(expr instanceof Call)) {
+          continue;
+        }
+        val = expr.variable.unwrapAll();
+        if (!(val instanceof Code && !expr.args.length || val instanceof Value && val.base instanceof Code && val.properties.length === 1 && ((_ref2 = val.properties[0].name) != null ? _ref2.value : void 0) === 'call')) {
+          continue;
+        }
+        fn = val.base || val;
+        ref = new Literal(o.scope.freeVariable('fn'));
+        base = new Value(ref);
+        args = compact([name, index]);
+        if (this.object) {
+          args.reverse();
+        }
+        for (i = 0, _len2 = args.length; i < _len2; i++) {
+          arg = args[i];
+          fn.params.push(new Param(args[i] = new Literal(arg)));
+        }
+        if (val.base) {
+          _ref3 = [base, val], val.base = _ref3[0], base = _ref3[1];
+          args.unshift(new Literal('this'));
+        }
+        body.expressions[idx] = new Call(base, args);
+        defs += this.tab + new Assign(ref, fn).compile(o, LEVEL_TOP) + ';\n';
+      }
+      return defs;
+    };
     return For;
   })();
   exports.Switch = (function() {

src/nodes.coffee

@@ -1335,6 +1335,7 @@ exports.For = class For extends Base
         when -1 then '--'
         else (if pvar < 0 then ' -= ' + pvar.slice 1 else ' += ' + pvar)
     varPart = idt + namePart + ';\n' if namePart
+    defPart += @pluckDirectCall o, body, name, index unless @pattern
     code = guardPart + varPart
     unless body.isEmpty()
       if o.level > LEVEL_TOP or @returns
@@ -1348,6 +1349,30 @@ exports.For = class For extends Base
     code = '\n' + code + '\n' + @tab if code
     defPart + @tab + "for (#{forPart}) {#{code}}" + retPart
 
+  pluckDirectCall: (o, body, name, index) ->
+    defs = ''
+    for expr, idx in body.expressions
+      expr = expr.unwrapAll()
+      continue unless expr instanceof Call
+      val = expr.variable.unwrapAll()
+      continue unless val instanceof Code and not expr.args.length or
+        val instanceof Value and val.base instanceof Code and
+        val.properties.length is 1 and
+        val.properties[0].name?.value is 'call'
+      fn    = val.base or val
+      ref   = new Literal o.scope.freeVariable 'fn'
+      base  = new Value ref
+      args  = compact [name, index]
+      args.reverse() if @object
+      for arg, i in args
+        fn.params.push new Param args[i] = new Literal arg
+      if val.base
+        [val.base, base] = [base, val]
+        args.unshift new Literal 'this'
+      body.expressions[idx] = new Call base, args
+      defs += @tab + new Assign(ref, fn).compile(o, LEVEL_TOP) + ';\n'
+    defs
+
 #### Switch
 
 # A JavaScript *switch* statement. Converts into a returnable expression on-demand.