RfC for language feature: rvalue struct

[Salih Dincer]

On Thursday, 26 January 2023 at 03:39:14 UTC, FeepingCreature 
wrote:
>
> The problem is that then you can't do
>
> ```
> Foo foo;
> foo = Foo(2, [3]);
> ```
>
> And that may look easy to avoid, but there's a plethora of bugs 
> where for instance Phobos does just that.

No problem:

```d
struct Foo(T)
{
   import std.conv   : to;
   import std.traits : ImmutableOf;

   this(R)(R bar, R[] baz)
   {
     this.bar = bar;
     this.baz = baz.to!(ImmutableOf!T[]);
   }

   immutable:
     T bar;
     T[] baz;
}

void main()
{
   immutable arr = [9, 8, 7];
   auto num1 = Foo!int(1, [2, 3, 4]);
   auto num2 = Foo!int(1, arr);

   string str = "bcd";
   auto str1 = Foo!char('a', str.dup);
   auto str2 = Foo!char('a', str);
}
```

SDB at 79