RFC: std.sumtype (adding sumtype to Phobos)

[jmh530]

On Wednesday, 25 November 2020 at 17:53:41 UTC, bachmeier wrote:
> [snip]
>
> If that's the case, I agree that it's a good thing to show. You 
> might consider having a clean version of toFahrenheit and then 
> something like
>
> // SumType can be used in @safe/pure/nothrow/@nogc code
> pure @safe @nogc nothrow
> void freeze(ref Temperature t)
>
> Whatever you do with that, it clears up my concern and I would 
> like to see this added to Phobos.

In general, if you can call a function in a block with all the 
attributes, then you can call it without them all too, but that 
may not be known to someone who has not made much use of them.