"A function that returns the result of applying the given 
 [[function|resulting]] to the [[item|Entry.item]] 
 of a given [[Entry]], discarding its `key`.
     
     Map<String,List<Item>> map = ... ;
     {Item?*} topItems = map.map(forItem(List<Item>.first));"​
​see (`function forKey`)
​tagged("Functions")
​shared Result forItem<Item,Result>(Result resulting(Item item))
            (Object->Item entry)
        => resulting(entry.item);
​