Proposal: Supporting C# 7 deconstruction of certain types. #19397
Description
Background
C# 7 added support for deconstruction of user-defined types via a Deconstruct(out ...) method. (see it in action) It would make sense to be able to use this feature with tuple-like types such as KeyValuePair and DictionaryEntry.
Proposal
public struct KeyValuePair<TKey, TValue>
{
// BLOCKED (do not add now): [EditorBrowsable(EditorBrowsableState.Never)]
public void Deconstruct(out TKey key, out TValue value);
}
public struct DictionaryEntry
{
// BLOCKED (do not add now): [EditorBrowsable(EditorBrowsableState.Never)]
public void Deconstruct(out object key, out object value);
}Usage
public void MyDictionaryMethod()
{
var dict = new Dictionary<int, string>();
dict.Add(1, "2");
var (one, two) = dict.First();
}