https://issues.dlang.org/show_bug.cgi?id=21533

          Issue ID: 21533
           Summary: dtoh: Non-type aliases aren't ignored
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: kinke@gmx.net

E.g., in frontend.h:

template <typename T>
struct Array
{
    [...]
    typedef length opDollar;
    typedef length dim;
    [...]
};

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