spec/helpers/dom-utils.js
function isIE ( opts ) {
    var ver = getIEVersion(),
        isMatch = ver !== 0;

    opts || ( opts = {} );

    if ( isMatch && opts.eq ) isMatch = ver === opts.eq;
    if ( isMatch && opts.lt ) isMatch = ver < opts.lt;
    if ( isMatch && opts.lte ) isMatch = ver <= opts.lte;
    if ( isMatch && opts.gt ) isMatch = ver > opts.gt;
    if ( isMatch && opts.gte ) isMatch = ver >= opts.gte;

    return isMatch;
}
function isIE ( opts ) {
    var ver = getIEVersion(),
        isMatch = ver !== 0;

    opts || ( opts = {} );

    if ( isMatch && opts.eq ) isMatch = ver === opts.eq;
    if ( isMatch && opts.lt ) isMatch = ver < opts.lt;
    if ( isMatch && opts.lte ) isMatch = ver <= opts.lte;
    if ( isMatch && opts.gt ) isMatch = ver > opts.gt;
    if ( isMatch && opts.gte ) isMatch = ver >= opts.gte;

    return isMatch;
}
function isIE ( opts ) { var ver = getIEVersion ( ) , isMatch = ver !== 0 ; opts || ( opts = { } ) ; if ( isMatch && opts . eq ) isMatch = ver === opts . eq ; if ( isMatch && opts . lt ) isMatch = ver < opts . lt ; if ( isMatch && opts . lte ) isMatch = ver <= opts . lte ; if ( isMatch && opts . gt ) isMatch = ver > opts . gt ; if ( isMatch && opts . gte ) isMatch = ver >= opts . gte ; return isMatch ; }
Detects IE.

Can use a version requirement. A range can also be specified, e.g. with an option like { gte: 8, lt: 11 }.

@param {Object} [opts]
@param {number} [opts.eq]   the IE version must be as specified
@param {number} [opts.lt]   the IE version must be less than the one specified
@param {number} [opts.lte]  the IE version must be less than or equal to the one specified
@param {number} [opts.gt]   the IE version must be greater than the one specified
@param {number} [opts.gte]  the IE version must be greater than or equal to the one specified
Detects IE .