https://issues.dlang.org/show_bug.cgi?id=12676

--- Comment #1 from Andrej Mitrovic <andrej.mitrovich@gmail.com> ---
Sorry, the example is a bit wrong. Fixed:

-----
template TemplAlias1(
    alias x = C  // default
) { }

template TemplAlias2(
    alias x : C  // specialization
) { }

template TemplAlias3(
    alias x : C = C  // default = C, specializes to C
) { }

void main()
{
    alias a = TemplAlias1!();
    alias b = TemplAlias2!(C);
    alias c = TemplAlias3!();
}
-----

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https://issues.dlang.org/show_bug.cgi?id=12676

--- Comment #2 from Andrej Mitrovic <andrej.mitrovich@gmail.com> ---
Here:

-----
class C { }
class D : C { }

template TemplAlias(
    alias x : D = C
) { }
-----

For some reason in the parser isDeclaration() returns false for ": Type", but
true for "= Type", and either a parseType() or a parseCondExp() is taken.Later
in in the semantic phase the alias class tries to evaluate D as an expression
rather than as a type so it fails.

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https://issues.dlang.org/show_bug.cgi?id=12676

Andrej Mitrovic <andrej.mitrovich@gmail.com> changed:

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

--- Comment #3 from Andrej Mitrovic <andrej.mitrovich@gmail.com> ---
Not a bug, aliases work on literals and expressions, not types.

--

https://issues.dlang.org/show_bug.cgi?id=12676

Andrej Mitrovic <andrej.mitrovich@gmail.com> changed:

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

--- Comment #4 from Andrej Mitrovic <andrej.mitrovich@gmail.com> ---
Ok, the OP example wasn't supported, but this must be a bug:

-----
template Templ1() { }

template Templ2
(
    alias T : Templ1 = Templ1,
) { }
-----

test.d(5): Error: Cannot interpret Templ1() at compile time

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https://issues.dlang.org/show_bug.cgi?id=12676

Iain Buclaw <ibuclaw@gdcproject.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P1                          |P3

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https://issues.dlang.org/show_bug.cgi?id=12676

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

https://github.com/dlang/dmd/issues/17656

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

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