gistfile1.txt

function createExchange(exchangeData) {
    
    function init(exchange, orderType) {
        if (!exchange[orderType]) {
            exchange[orderType] = {};
            exchange[orderType].volumes = {};
            exchange[orderType].prices = createBinaryHeap();
        }
    }
    
    var cloned = $.extend(true, {}, exchangeData);
    cloned.trades = [];
    init(cloned, BUY);
    init(cloned, SELL);
    return cloned;
    
}