https://issues.dlang.org/show_bug.cgi?id=12884

--- Comment #1 from Nils <nilsbossung@googlemail.com> ---
https://github.com/D-Programming-Language/dmd/pull/3654

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https://issues.dlang.org/show_bug.cgi?id=12884

Kenji Hara <k.hara.pg@gmail.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |INVALID

--- Comment #2 from Kenji Hara <k.hara.pg@gmail.com> ---
With class types, the possibility of implicit class reference conversion from
derived D to base class B is always determined in type system.
In other words, conversion from immutable D to mutable B is a defined but
disabled by default, and 'alias this' cannot override it.
(Note that 'alias this' is invoked when the conversion is _not_ defined)

So, 'alias this' never be considered in the case, and this is invalid issue.

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