https://issues.dlang.org/show_bug.cgi?id=20777

          Issue ID: 20777
           Summary: User defined types as anonymous enums basetype, fail
                    to compile.
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: crazymonkyyy@gmail.com

>struct fooint{
>  enum isfoo=true;
>  enum isbar=false;
>  int i;
>  auto opBinary(string op:"+")(int j){
>    return fooint(i+j);
>  }
>  alias i this;
>  @property fooint max(){return fooint(int.max);}
>}
>static assert(fooint(0)+1 != fooint(0).max);
>static assert(fooint(0)+1 != fooint(0));
>enum foolist {hi=fooint(0),bye,fizz,buzz}
>//no property max for type fooint, did you mean bar.fooint.max

"If there is no AssignExpression and it is not the first EnumMember, it is given the value of the previous EnumMember+1. If the value of the previous EnumMember is the .max property if the previous EnumMember's type, it is an error. If the value of the previous EnumMember+1 is the same as the value of the previous EnumMember, it is an error."

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