public static IEnumerable <Value> Select <Key, Value>(this KeyedCollection <Key, Value> keyedCollection, IEnumerable <Key> keys)
where Key : notnull
where Value : notnull
{
foreach (Key key in keys)
{
if (keyedCollection.Peek(key, out Value value))
{
yield return(value);
}
}
}
public static bool CastedPeek <Key, Value, Result>(this KeyedCollection <Key, Value> keyedCollection, Key key, out Result result)
where Key : notnull
where Value : notnull
where Result : notnull, Value
{
if (keyedCollection.Peek(key, out Value value) && value is Result match)
{
result = match;
return(true);
}
result = default !;