isInt.js

/**
 * A simple type check for integers
 *
 * Interprets integer valued strings as integers (e.g. '22' will return true).
 *
 * @param value
 * @returns {boolean}
 */
function isInt(value) {
    var x;
    if (isNaN(value)) {
        return false;
    }
    x = parseFloat(value);
    return (x | 0) === x;
}