Re: How to define operator =?UTF-8?B?ImNvbnN0?= char =?UTF-8?B?KiI=?= of enumerated type defined inside a class

From:
Sam <sam@email-scan.com>
Newsgroups:
comp.lang.c++
Date:
Wed, 24 Sep 2008 06:10:08 -0500
Message-ID:
<cone.1222254608.28545.7466.500@commodore.email-scan.com>
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Bill Davy writes:

I want to be able to write (const char*)v where v is an item of type
Class::ToolTypeT where ToolTypeT is an enumeration and I've tried
everything that looks sensible. There's an ugly solution, but surely this is
possible?


You can't really do this with merely an enum. You can, however, define a
class that, essentially, acts like an enum.

class Class {

public:

    static const int a=0;
    static const int b=1;
    static const int c=2;

    class ToolTypeT {
        int v;

    public:
        ToolTypeT(int i): v(i) {}

        ToolType &operator=(int i) { v=i; return *this; }

        operator int() const { return v; }

        operator const char *();
    };
};

You can use this Class::ToolTypeT pretty much like an enumeration. Class::a,
Class::b, Class::c, etc. are your enumerator values. And, you can supply a
meaningful operator const char *().

And, with a few more tweaks, you can add additional type-safety to the whole
schema.

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