https://issues.dlang.org/show_bug.cgi?id=23669

--- Comment #1 from Paul Backus <snarwin+bugzilla@gmail.com> ---
The error is caused by the way DMD lowers `a.length += 1;`, which can be seen using the -vcg-ast switch:

---
(string[]* __arraylength2 = &this.a;) , _d_arraysetlengthT(*__arraylength2,
(*__arraylength2).length + 1LU);
---

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https://issues.dlang.org/show_bug.cgi?id=23669

Paul Backus <snarwin+bugzilla@gmail.com> changed:

           What    |Removed                     |Added
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           Keywords|                            |rejects-valid

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https://issues.dlang.org/show_bug.cgi?id=23669

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |pull

--- Comment #2 from Dlang Bot <dlang-bot@dlang.rocks> ---
@ntrel created dlang/dmd pull request #14865 "Fix Issue 23669 - [DIP1000] Compound assignment to length of slice me…" fixing this issue:

- Fix Issue 23669 - [DIP1000] Compound assignment to length of slice member variable in scope method fails

https://github.com/dlang/dmd/pull/14865

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https://issues.dlang.org/show_bug.cgi?id=23669

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

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

--- Comment #3 from Dlang Bot <dlang-bot@dlang.rocks> ---
dlang/dmd pull request #14865 "Fix Issue 23669 - [DIP1000] Compound assignment to length of slice me…" was merged into master:

- 22c74814de7b19fcd92d22f73f093c22d53060dd by Nick Treleaven:
  Fix Issue 23669 - [DIP1000] Compound assignment to length of slice member
variable in scope method fails

https://github.com/dlang/dmd/pull/14865

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