https://issues.dlang.org/show_bug.cgi?id=20884

Dlang Bot <dlang-bot@dlang.rocks> changed:

           What    |Removed                     |Added
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           Keywords|                            |pull

--- Comment #1 from Dlang Bot <dlang-bot@dlang.rocks> ---
@BorisCarvajal created dlang/dmd pull request #11200 "Fix Issue 20884 - Using getMember with a type as first argument can l…" fixing this issue:

- Fix Issue 20884 - Using getMember with a type as first argument can lose type qualifiers.

https://github.com/dlang/dmd/pull/11200

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https://issues.dlang.org/show_bug.cgi?id=20884

Boris Carvajal <boris2.9@gmail.com> changed:

           What    |Removed                     |Added
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             Blocks|                            |13343


Referenced Issues:

https://issues.dlang.org/show_bug.cgi?id=13343
[Issue 13343] Strange behaviour aliasing struct members
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https://issues.dlang.org/show_bug.cgi?id=20884

Dlang Bot <dlang-bot@dlang.rocks> changed:

           What    |Removed                     |Added
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             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED

--- Comment #2 from Dlang Bot <dlang-bot@dlang.rocks> ---
dlang/dmd pull request #11200 "Fix Issue 20884 - Using getMember with a type as first argument can l…" was merged into stable:

- aa33b64dfbe78a6621314472e1ad88ea5aa2afcb by Boris Carvajal:
  Fix Issue 20884 - Using getMember with a type as first argument can lose type
qualifiers.

https://github.com/dlang/dmd/pull/11200

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https://issues.dlang.org/show_bug.cgi?id=20884

Mathias LANG <pro.mathias.lang@gmail.com> changed:

           What    |Removed                     |Added
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             Status|RESOLVED                    |REOPENED
                 CC|                            |pro.mathias.lang@gmail.com
         Resolution|FIXED                       |---

--- Comment #3 from Mathias LANG <pro.mathias.lang@gmail.com> ---
This wasn't fully fixed. Ran into this one today:
```
pragma(msg, __VERSION__);

template FieldRef (T, string name)
{
        alias Ref = __traits(getMember, T, name);

        alias Type1 = typeof(Ref);
        alias Type2 = typeof(__traits(getMember, T, name));

    pragma(msg, "Instantiating FieldRef: ", T, ".", name, " => ", Type1, "
versus ", Type2);
}

struct Config
{
        Inner inner;
}

struct Inner
{
        char[] value;
}

alias IConfig = immutable(Config);
alias Result = FieldRef!(IConfig, `inner`);
alias ResultBis = FieldRef!(Result.Type2, "value");
```

Result:
```
2098L
Instantiating FieldRef: immutable(Config).inner => Inner versus
immutable(Inner)
Instantiating FieldRef: immutable(Inner).value => char[] versus
immutable(string)
```

As you can see, using the `__traits` directly works, but using an `alias` to the `__traits` still has the bug. This was tested with nightly (2.098), the aforementioned PR was released in v2.092.

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https://issues.dlang.org/show_bug.cgi?id=20884

--- Comment #4 from Boris Carvajal <boris2.9@gmail.com> ---
That is an alias bug, replace the getMember trait with 'mixin("T." ~ name)' in
your code and the result is the same.
```
alias Ref = mixin("T." ~ name);
...
alias Type2 = typeof(mixin("T." ~ name));
```

I think it's duplicated of issue 2704 (really old, probably there are more
reports out there).
Some different but related bugs are issue 13343 and issue 20863.

There is a generic alias problem with respect to aggregate types (that have qualifiers) because the duality of them being a symbol and type at the same time, it also extends when interacting with their members.

This report was about fixing '__traits(getMember)' so maybe you should move the test case to 2704 and keep this closed.

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https://issues.dlang.org/show_bug.cgi?id=20884

Iain Buclaw <ibuclaw@gdcproject.org> changed:

           What    |Removed                     |Added
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           Priority|P1                          |P3

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https://issues.dlang.org/show_bug.cgi?id=20884

--- Comment #5 from dlangBugzillaToGithub <robert.schadek@posteo.de> ---
THIS ISSUE HAS BEEN MOVED TO GITHUB

https://github.com/dlang/dmd/issues/19713

DO NOT COMMENT HERE ANYMORE, NOBODY WILL SEE IT, THIS ISSUE HAS BEEN MOVED TO GITHUB

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