https://issues.dlang.org/show_bug.cgi?id=15182

          Issue ID: 15182
           Summary: only(enums) refused
           Product: D
           Version: D2
          Hardware: x86
                OS: Windows
            Status: NEW
          Severity: normal
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: bearophile_hugs@eml.cc

void main() {
    import std.range: only;
    enum Test { A }
    only(Test.A, Test.A);
}

dmd v2.067:

...\src\phobos\std\range\package.d(6046): Error: cannot implicitly convert
expression (0) of type int to Test[2]
test.d(4): Error: template instance std.range.only!(Test, Test) error
instantiating

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