[Proposal] Allow unboxing of Nullable<T> with HasValue and/or "is not null" pattern

[datvm]

Motivation

Currently after checking if a Nullable<T> has value or not (is null or not), we need another formal line to declare a non-nullable value of it:

if (skipId.HasValue)
{
	var v = skipId.Value;
	query = query
		.Where(q => q.Id > v);

	// Other code that use v
}

Proposal

Allow declaration of a variable right after Nullable<T>.HasValue property and/or in a is not null pattern:

if (skipId.HasValue v)
{
	query = query
		.Where(q => q.Id > v);

	// Other code that use v
}

if (skipId is not null v)
{
	query = query
		.Where(q => q.Id > v);

	// Other code that use v
}

[jnm2]

The syntax that works today (C# 8+) is if (skipId is { } v) but it's not as intuitive.

@CyrusNajmabadi You talked about being interested in is not null v a while back. What do you think?

[datvm]

Just want to chime in that I am more favored of skipId.HasValue v because it also feels more natural (skipId has value v) but I am okay with either or both.

[CyrusNajmabadi]

I'm still interested in it. But it's way way down on my list of what I think is important