Proposal: Allow the name of an out variable to be omitted if it is not used

[jmairboeck]

It should be allowed to omit the variable name of a variable declared in an out expression, if the variable is not going to be used (similar to the catch clause for example), like this:

string str = ...
var isValidInt = int.TryParse(str, out int); // or out var
// the actual value is not needed here

Currently, when just saying out int, it is considered an "invalid expression". In the out var case, it is reported as "identifier var not found" (because var is a contextual keyword).

[CyrusNajmabadi]

Use _. https://docs.microsoft.com/en-us/dotnet/csharp/discards

string str = ...
var isValidInt = int.TryParse(str, out _);