(function() {
  this.Tether.modules.push({
    position: function(_arg) {
      var left, result, shift, shiftLeft, shiftTop, top, _ref;
      top = _arg.top, left = _arg.left;
      if (!this.options.shift) {
        return;
      }
      result = function(val) {
        if (typeof val === 'function') {
          return val.call(this, {
            top: top,
            left: left
          });
        } else {
          return val;
        }
      };
      shift = result(this.options.shift);
      if (typeof shift === 'string') {
        shift = shift.split(' ');
        shift[1] || (shift[1] = shift[0]);
        shiftTop = shift[0], shiftLeft = shift[1];
        shiftTop = parseFloat(shiftTop, 10);
        shiftLeft = parseFloat(shiftLeft, 10);
      } else {
        _ref = [shift.top, shift.left], shiftTop = _ref[0], shiftLeft = _ref[1];
      }
      top += shiftTop;
      left += shiftLeft;
      return {
        top: top,
        left: left
      };
    }
  });

}).call(this);