https://issues.dlang.org/show_bug.cgi?id=13540

          Issue ID: 13540
           Summary: Meaningless alias declaration is accepted
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Keywords: accepts-invalid
          Severity: normal
          Priority: P1
         Component: DMD
          Assignee: nobody@puremagic.com
          Reporter: k.hara.pg@gmail.com

The alias declaration:

   alias int[] f(TemplateTypeParam)(int arg);

is just treated as:

   alias int[] f(int arg);
   static assert(is(f* == int[] function(int));

and the redundant template parameter list is just ignored.

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