Using underscore.js methods to make validation logic simplier

check_input.js

function checkInput(id, msgId) {
    /*
     * someFieldsMissingValue is true if at least one input element's value is empty
     */
    var someFieldsMissingValue = _.some(
        $("form input"),
        function(aDom) { 
            return _.isEmpty($(aDom).val());
        }
    );
    
    /*
     * someErrors is true if at least one element's contains error message
     */
    var someErrors = _.some(
        $("form .errorMsg"),
        function(aDom) { 
            return !_.isEmpty($(aDom).html());
        }
    );
    if (someFieldsMissingValue || someErrors) {
        disableCreateBtn();
    } else {
        enableCreateBtn();
    }
}