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

[d-bugmail--- via Digitalmars-d-bugs]

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

github-bugzi...@puremagic.com changed:

   What|Removed |Added

 Status|REOPENED|RESOLVED
 Resolution|--- |FIXED

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

[d-bugmail--- via Digitalmars-d-bugs]

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

--- Comment #8 from github-bugzi...@puremagic.com ---
Commits pushed to master at https://github.com/dlang/dmd

https://github.com/dlang/dmd/commit/2dbc2bd85d5e5a55a3bcbf362c60cb0648102a73
fix Issue 18282 part 2

https://github.com/dlang/dmd/commit/bbe466b97fe5d2fa9f2914937f42079a987579d2
Merge pull request #8045 from WalterBright/fix18282-2

fix Issue 18282 part 2
merged-on-behalf-of: Walter Bright 

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

[d-bugmail--- via Digitalmars-d-bugs]

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

--- Comment #7 from Walter Bright  ---
https://github.com/dlang/dmd/pull/8045

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

[d-bugmail--- via Digitalmars-d-bugs]

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

ag0aep6g  changed:

   What|Removed |Added

 Status|RESOLVED|REOPENED
 Resolution|FIXED   |---

--- Comment #6 from ag0aep6g  ---
(In reply to Walter Bright from comment #4)
> https://github.com/dlang/dmd/pull/8030

That seems to have fixed this snippet from comment #2:


string* f() @safe
{
scope string*[] ls;
return ls[0];
}


But the original test case still fails:


void main() @safe
{
string foo = "foo";
scope string*[] ls;
ls ~=  /* Error. But this works: ls = ls ~  */
}


Looks like the actual issue hasn't been fixed. Reopening.

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

[d-bugmail--- via Digitalmars-d-bugs]

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

github-bugzi...@puremagic.com changed:

   What|Removed |Added

 Status|REOPENED|RESOLVED
 Resolution|--- |FIXED

--

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

[d-bugmail--- via Digitalmars-d-bugs]

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

--- Comment #5 from github-bugzi...@puremagic.com ---
Commits pushed to master at https://github.com/dlang/dmd

https://github.com/dlang/dmd/commit/ac0224287fd16d293081059acef7c23b94212a7b
fix Issue 18282 - [Scope][DIP1000]Assignment of local variable to  variable not
recognized by compiler

https://github.com/dlang/dmd/commit/718350da81d5c2d1f18e0eb7b6e6ec69d1e69c34
Merge pull request #8030 from WalterBright/fix18282

fix Issue 18282 - [Scope][DIP1000]Assignment of local variable to  va…
merged-on-behalf-of: Mike Franklin 

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

[d-bugmail--- via Digitalmars-d-bugs]

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

Carsten Blüggel  changed:

   What|Removed |Added

 CC||chi...@posteo.net

--

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

[d-bugmail--- via Digitalmars-d-bugs]

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

--- Comment #4 from Walter Bright  ---
https://github.com/dlang/dmd/pull/8030

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

[d-bugmail--- via Digitalmars-d-bugs]

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

Walter Bright  changed:

   What|Removed |Added

 Status|RESOLVED|REOPENED
 Resolution|INVALID |---

--- Comment #3 from Walter Bright  ---
I'll reopen it and look at it again.

--

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

[d-bugmail--- via Digitalmars-d-bugs]

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

ag0ae...@gmail.com changed:

   What|Removed |Added

 CC||ag0ae...@gmail.com

--- Comment #2 from ag0ae...@gmail.com ---
(In reply to Walter Bright from comment #1)
> (In reply to Mike Franklin from comment #0)
> > void main() @safe
> > {
> > string foo = "foo";
> > scope string*[] ls;
> > ls ~= 
> > }
> > 
> > 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.

I assume that you don't mean `ls[]` literally, but rather that the elements of
`ls` aren't `scope`, right?

That means, it should be okay to return `ls[0]` because that's not `scope`,
right? But that doesn't work:


string* f() @safe
{
scope string*[] ls;
return ls[0]; /* Error: scope variable ls may not be returned */
}


On the other hand, this works:


void main() @safe
{
string foo = "foo";
scope string*[] ls;
ls = ls ~ 
}


The only difference from the original code is `ls ~= ` -> `ls = ls ~
`. Those two assignments should be equivalent [1], no? Either both should
be accepted, or both should be rejected.


[1] https://dlang.org/spec/expression.html#assignment_operator_expressions

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

[d-bugmail--- via Digitalmars-d-bugs]

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

Walter Bright  changed:

   What|Removed |Added

 Status|NEW |RESOLVED
 CC||bugzi...@digitalmars.com
 Resolution|--- |INVALID

--- Comment #1 from Walter Bright  ---
(In reply to Mike Franklin from comment #0)
> void main() @safe
> {
> string foo = "foo";
> scope string*[] ls;
> ls ~= 
> }
> 
> 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 ~= 
> }
> 
> 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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[Issue 18282] [Scope][DIP1000]Assignment of local variable to `scope` variable not recognized by compiler

[d-bugmail--- via Digitalmars-d-bugs]

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

Mike Franklin  changed:

   What|Removed |Added

Summary|Assignment of local |[Scope][DIP1000]Assignment
   |variable to `scope` |of local variable to
   |variable not recognized by  |`scope` variable not
   |compiler|recognized by compiler

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