node_modules/tui-dom/src/js/domevent.js
/**
 * test if browser is IE8 and earlier(IE6 or IE7)
 * @returns {boolean} - whether browser is IE6 ~ 8 or not
 * @private
 */
test if browser is IE8 and earlier
@returns {boolean} - whether browser is IE6 ~ 8 or not
@private
test if browser is IE8 and earlier @returns { boolean } - whether browser is IE6 ~ 8 or not @private
function _isIE8AndEarlier() {
    return (navigator.userAgent.indexOf('msie 8') > -1)
        || (navigator.userAgent.indexOf('msie 7') > -1)
        || (navigator.userAgent.indexOf('msie 6') > -1);
}
function _isIE8AndEarlier ( ) { return ( navigator . userAgent . indexOf ( 'msie 8' ) > - 1 ) || ( navigator . userAgent . indexOf ( 'msie 7' ) > - 1 ) || ( navigator . userAgent . indexOf ( 'msie 6' ) > - 1 ) ; }
test if browser is IE8 and earlier(IE6 or IE7)
 @returns {boolean} - whether browser is IE6 ~ 8 or not
 @private
test if browser is IE8 and earlier ( IE6 or IE7 ) @returns { boolean } - whether browser is IE6 ~ 8 or not @private