src/base/util.js
function(_list,_low,_high){
            if (_low>_high) return -1;
            var _middle = Math.ceil((_low+_high)/2),
                _result = _docheck(_list[_middle],_middle,_list);
            if (_result==0)
                return _middle;
            if (_result<0)
                return _doSearch(_list,_low,_middle-1);
            return _doSearch(_list,_middle+1,_high);
        }
function(_list,_low,_high){
            if (_low>_high) return -1;
            var _middle = Math.ceil((_low+_high)/2),
                _result = _docheck(_list[_middle],_middle,_list);
            if (_result==0)
                return _middle;
            if (_result<0)
                return _doSearch(_list,_low,_middle-1);
            return _doSearch(_list,_middle+1,_high);
        }
function ( _list , _low , _high ) { if ( _low > _high ) return - 1 ; var _middle = Math . ceil ( ( _low + _high ) / 2 ) , _result = _docheck ( _list [ _middle ] , _middle , _list ) ; if ( _result == 0 ) return _middle ; if ( _result < 0 ) return _doSearch ( _list , _low , _middle - 1 ) ; return _doSearch ( _list , _middle + 1 , _high ) ; }
do binary search
do binary search