dep_scope_type.dd

`scope` as a type constraint on class, struct, and enum declarations is deprecated.

`scope` as a type constraint on class declarations was meant to force users
of a class to `scope` allocate it, which resulted in the class being placed
on the stack rather than GC-allocated. While it has been scheduled for
deprecation for quite some time, the compiler will emit a deprecation warning
on usage starting from this release.

`scope` as a type constraint on struct or enum declarations has never had any
effect, and has been deprecated as well.

---
scope class C { }  // Deprecation: `scope` as a type constraint is deprecated. Use `scope` at the usage site.
scope struct S { } // Ditto
scope enum E { }   // Ditto
---

Using `scope` to stack-allocate `class` is still suported,
only the type constraint is deprecated.

---
class C { }

void main () @nogc
{
    scope c = new C;
}
---