function _getMatches(character, modifiers, e, sequenceName, combination, level) {
            var i;
            var callback;
            var matches = [];
            var action = e.type;

            // if there are no events related to this keycode
            if (!self._callbacks[character]) {
                return [];
            }

            // if a modifier key is coming up on its own we should allow it
            if (action == 'keyup' && _isModifier(character)) {
                modifiers = [character];
            }

            // loop through all callbacks for the key that was pressed
            // and see if any of them match
            for (i = 0; i < self._callbacks[character].length; ++i) {
                callback = self._callbacks[character][i];

                // if a sequence name is not specified, but this is a sequence at
                // the wrong level then move onto the next match
                if (!sequenceName && callback.seq && _sequenceLevels[callback.seq] != callback.level) {
                    continue;
                }

                // if the action we are looking for doesn't match the action we got
                // then we should keep going
                if (action != callback.action) {
                    continue;
                }

                // if this is a keypress event and the meta key and control key
                // are not pressed that means that we need to only look at the
                // character, otherwise check the modifiers as well
                //
                // chrome will not fire a keypress if meta or control is down
                // safari will fire a keypress if meta or meta+shift is down
                // firefox will fire a keypress if meta or control is down
                if ((action == 'keypress' && !e.metaKey && !e.ctrlKey) || _modifiersMatch(modifiers, callback.modifiers)) {

                    // when you bind a combination or sequence a second time it
                    // should overwrite the first one.  if a sequenceName or
                    // combination is specified in this call it does just that
                    //
                    // @todo make deleting its own method?
                    var deleteCombo = !sequenceName && callback.combo == combination;
                    var deleteSequence = sequenceName && callback.seq == sequenceName && callback.level == level;
                    if (deleteCombo || deleteSequence) {
                        self._callbacks[character].splice(i, 1);
                    }

                    matches.push(callback);
                }
            }

            return matches;
        }
finds all callbacks that match based on the keycode, modifiers,
and action

@param {string} character
@param {Array} modifiers
@param {Event|Object} e
@param {string=} sequenceName - name of the sequence we are looking for
@param {string=} combination
@param {number=} level
@returns {Array}