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Bugzilla references

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub fetch digger
dub run digger -- build "stable + dmd#10197"

This is a pretty simple fix, might as well target stable.

Rebased on stable, std.meta import removed.

Looks like you also improved an error message in the process :)

Indeed

Test fail_compilation/fail8262.d failed: 
expected:
----
fail_compilation/fail8262.d(32): Error: cannot interpret `Tuple8262!1` at compile time
fail_compilation/fail8262.d(27): Error: template instance `fail8262.T8262!(Tuple8262!1)` error instantiating
fail_compilation/fail8262.d(19): Error: cannot implicitly convert expression `S(0)` of type `S` to `int`
----
actual:
----
fail_compilation/fail8262.d(32): Error: initializer must be an expression, not `Tuple8262!1`
fail_compilation/fail8262.d(27): Error: template instance `fail8262.T8262!(Tuple8262!1)` error instantiating
fail

core.exception.AssertError@dmd/dinterpret.d(5074): Assertion failure

Seems to be some places where CTFE is too defensive in what types of expressions it'll accept. Maybe fixed now? Let's run the tests.

Seems to like it, you still need to correct the error message above.

Now that this needed one or two more changes before going green, should this still go on stable or should I move back to master?

Stable is fine.

dinterpret.d is not supposed to handle type-exps.
Nor' is the rest of the compiler really.
Prepare for unforeseen consequences.

Ah damn, that sounds worrying. Noting that I don't really know the implications, and relied on the testsuite, afaics the problem happened originally because in enum string[] foo = [AliasSeq!()], the () is a type, not a value... the changes are just to allow the () to propagate to whatever part of the compiler notices this case ordinarily.

All the tests were green though, so...

Maybe I should have nailed things down so that only this specific case was allowed.