[Issue 19093] 'cannot alias itself' when using a template instantiation in a template parameter

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=19093

--- Comment #2 from Simen Kjaeraas <simen.kjaras at gmail.com> ---
Works better if Foo's parameter is called something else:

alias Foo(U) = U; // undefined identifier T

Obviously you're right about the real problem, and the error message is a case
of bad diagnostic. However, I think you should be allowed to reuse the previous
template params.

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