gistfile1.txt

myAutoComplete._isIgnoreKey = (function (original) {

    return function (keyCode) {
        return (keyCode > 47 && keyCode < 58) || original.apply(this, arguments);
    }

})(myAutoComplete._isIgnoreKey);

// OR

myAutoComplete._sendQuery = (function (original) {

    return function (text) {
        if (/\D/.test(text)) {
            original.apply(this, arguments);
        }
    }

})(myAutoComplete._sendQuery);