Make target-typed new objects callable

[fandrei]

At the current moment, it's possible to write the code like this:

static readonly DateTime Test1 = (new DateTime(2020, 01, 01)).ToUniversalTime();

However, not like this:

static readonly DateTime Test2 = (new(2020, 01, 01)).ToUniversalTime();

I think that it would be useful to make it work in the second case, too.

[BlinD-HuNTeR]

I like this thing, but the problem is, you could only call methods that would return the exact same type of the variable.

[jnm2]

Yeah, and it also raises questions like: how long of a chain of calls could you construct? And how do you deal with overload resolution between methods that might or might not return the exact same type, depending on the exact types of the arguments passed?

[fandrei]

Yeah, and it also raises questions like: how long of a chain of calls could you construct? And how do you deal with overload resolution between methods that might or might not return the exact same type, depending on the exact types of the arguments passed?

Is it much different from the case when type name is specified explicitly? 🤷

[TahirAhmadov]

@fandrei the problem is, how do you determine the type? For example:

static readonly int Test1 = (new(2020, 01, 01)).Year;
static readonly DateTime Test2 = new(2020, 01, 01) + TimeSpan.FromDays(1);
static readonly TimeSpan Test3 = new(2020, 01, 01) - new(2010, 01, 01);

Should the above scenarios be supported? If so, how would you deduce that it should be the DateTime constructor in the new(...)?

[fandrei]

the problem is, how do you determine the type?

@TahirAhmadov we can just assume that new() with no type means the type specified on the left side of the assignment. After all, that's what target-typed new is supposed to mean.

[TahirAhmadov]

There definitely was an item requesting exactly this, and it was concluded that the complications here far outweigh the benefits. I can't find it, though.

[CyrusNajmabadi]

I never asked for subjective views.

You literally said:

I'm trying to figure out why the C# team guys consider some features unnecessary

This is a question on how we subjectively rank thinks. If you ask that question, you will get our subjective views on what makes one feature less necessary than another.

[HaloFour]

#8890 (reply in thread)

[CyrusNajmabadi]

No, I'm mostly interested in arguments "for" and "against", and comparison of such arguments.

This is subjective. If you ask for subjective responses, it's not ok to then reject them for being subjective.

However, if your arguments look weak to me

That's not my concern. You asked for opinions. Opinions are being provided. I personally have no interest in trying to convince you that my personal opinion is correct.