function evaluateEqualityExpression(lhs, rhs, op) {
        var result;

        // type checks
        var ltype = typeof lhs;
        var rtype = typeof rhs;

        if (ltype === 'undefined' || rtype === 'undefined') {
            // if either side is undefined, the result is false
            return false;
        }

        switch (op) {
            case '=':
                result = isDeepEqual(lhs, rhs);
                break;
            case '!=':
                result = !isDeepEqual(lhs, rhs);
                break;
        }
        return result;
    }
Evaluate equality expression against input data
@param {Object} lhs - LHS value
@param {Object} rhs - RHS value
@param {Object} op - opcode
@returns {*} Result