The packing algorithm is forgiving of all forms of JavaScript with one exception. You must correctly terminate all JavaScript statements with semi-colons. This includes function declarations.
Here is an example of correct, semi-colon terminated JavaScript:
// sample code var $input, $output; // notice the semi-colon at the END of function declarations onload = function() { $input = document.getElementById("input"); $output = document.getElementById("output"); _clearAll(true); }; function _packScript() { $output.value = pack($input.value); }; function _clearAll($focus) { $output.value = $input.value = ""; // the "if" statement is NOT terminated with a semi-colon if ($focus) { $input.focus(); } };