src/lib/collections/list.js
function (item, comparer, index, count) {
        index = index || 0;
        count = count || this.length;
        comparer = Comparer.from(comparer);

        return binarySearch(this, index, count, item, comparer.compare);
    }
function (item, comparer, index, count) {
        index = index || 0;
        count = count || this.length;
        comparer = Comparer.from(comparer);

        return binarySearch(this, index, count, item, comparer.compare);
    }
function ( item , comparer , index , count ) { index = index || 0 ; count = count || this . length ; comparer = Comparer . from ( comparer ) ; return binarySearch ( this , index , count , item , comparer . compare ) ; }
Searches a range of elements in the sorted List for an element using the specified comparer and returns the zero-based index of the element.
@param {Object} item The object to locate.
@param {Comparer=} comparer The Comparer implementation to use when comparing elements.
@param {Number=} index The zero-based starting index of the range to search.
@param {Number=} count The length of the range to search.
@returns {Number}
Searches a range of elements in the sorted List for an element using the specified comparer and returns the zero - based index of the element .