public static bool TryGetValue <TObject, TKey>(this IReadOnlyCache <TObject, TKey> cache, TKey key, [MaybeNullWhen(false)] out TObject value)
{
// ToDo
// Improve to not double query
if (cache.ContainsKey(key))
{
value = cache[key];
return(true);
}
value = default;
return(false);
}
public static IEnumerable <KeyValuePair <K, R> > SelectAgainst <K, V, R>(
this IReadOnlyCache <V, K> lhs,
IReadOnlyCache <V, K> rhs,
Func <K, V, V, R> selector,
out bool equal)
{
var ret = new List <KeyValuePair <K, R> >();
equal = lhs.Count == rhs.Count;
foreach (var item in lhs)
{
if (!rhs.ContainsKey(item.Key))
{
equal = false;
continue;
}
ret.Add(
new KeyValuePair <K, R>(
item.Key,
selector(item.Key, item.Value, rhs[item.Key])));
}
return(ret);
}