[Issue 18282] [Scope][DIP1000]Assignment of local variable to `scope` variable not recognized by compiler

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=18282

Walter Bright <bugzilla at digitalmars.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
                 CC|                            |bugzilla at digitalmars.com
         Resolution|---                         |INVALID

--- Comment #1 from Walter Bright <bugzilla at digitalmars.com> ---
(In reply to Mike Franklin from comment #0)
> void main() @safe
> {
>     string foo = "foo";
>     scope string*[] ls;
>     ls ~= &foo;
> }
> 
> Compile with `-dip1000`
> 
> onlineapp.d(5): Error: reference to local variable foo assigned to non-scope
> ls

While ls is scope, ls[] is not scope. Scope is not transitive, hence the
compiler error.


> The compiler doesn't seem to recognize that ls is attributed with `scope`. 
> However due to the way D's attributes are parsed, I'm not sure if it should
> actually be `scope string*[]`, `scope(string*)[]`, or `scope(string*[])`. 
> Anyway, if you use `scope()` (i.e. with parens) the compiler confuses it
> with `scope(exit)` and friends.
> 
> 
> void main() @safe
> {
>     string foo = "foo";
>     scope(string*[]) ls;
>     ls ~= &foo;
> }
> 
> Compile with `-dip1000`
> 
> onlineapp.d(4): Error: valid scope identifiers are exit, failure, or
> success, not string

Scope is a storage class, not a type constructor. (`const`, for example, is a
type constructor, and `static` is a storage class.)

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