yet another EventManager

event.js

function EventManager () {
    this._events = {};
}

EventManager.prototype = {
    _event: function (type) {
        var events = this._events[type];
        
        if (!events) {
            events = this._events[type] = {};
        }
        
        return events;
    },
    
    on: function (type, listener){
        this._event(type).push(listener);
    },

    trigger: function (type, data) {
        var event = {
            type: type,
            target: this
        };
        
        var events = this._event(type);        
        for (var i = 0, c = events.length; i < c; i++) {
            try {
                events[i](event, data);
            } catch (e) {}
        }
    },

    off: function (type, listener) {
        var events = this._event(type),
            index = events.indexOf(listener);
        
        if (index < 0) {
            return;
        }
        
        events.splice(index, 1);
    }
};

в 10-й строке {} это опечатка? разве не []?