--- /dev/null
+'use strict';
+
+var callable = require('./valid-callable')
+ , forEach = require('./for-each')
+
+ , call = Function.prototype.call;
+
+module.exports = function (obj, cb/*, thisArg*/) {
+ var o = {}, thisArg = arguments[2];
+ callable(cb);
+ forEach(obj, function (value, key, obj, index) {
+ o[call.call(cb, thisArg, key, value, this, index)] = value;
+ }, obj);
+ return o;
+};