Nathan Myers wrote:
>
> Haitao Zhao <jstwo@usa.net> wrote:
> >in global namespace:
> >typedef int BOOL
> >class a { public: virtual BOOL foo(); };
> >namespace MyBool {
> >    typedef bool BOOL
> >    struct b : a     {   bool foo(); };
> >}
> >when I compile it , the compiler didn't give any error...
> >Will this kind of define cause some potential bug or it's just works?
>
> Your compiler is broken.  b::foo has a signature that matches a::foo(),
> but with an incompatible return type.  The compiler should catch that.

I guess that the compiler doesn't support bool, and bool is
just #defined as int (a practice that I support for such
compilers).

--

Valentin Bonnard


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Haitao Zhao <jstwo@usa.net> wrote:
>in global namespace:
>typedef int BOOL
>class a { public: virtual BOOL foo(); };
>namespace MyBool {
>    typedef bool BOOL
>    struct b : a     {   bool foo(); };
>}
>when I compile it , the compiler didn't give any error...
>Will this kind of define cause some potential bug or it's just works?

Your compiler is broken.  b::foo has a signature that matches a::foo(),
but with an incompatible return type.  The compiler should catch that.

--
Nathan Myers
ncm@nospam.cantrip.org  http://www.cantrip.org/



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Haitao Zhao <haitao@hotmail.com> writes:

> I get a problem with namespace and typedef, does anyone know the
> following valid or not?

It is not valid. You can't have a virtual function return int in the
base class, and bool in the derived class - not even if you use
similar-looking typedefs :-)

Regards,
Martin
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Hi
I get a problem with namespace and typedef, does anyone know the
following valid or not?

the problem:

in global namespace, i defined a class:
class a {
public:
virtual BOOL foo();
...
};

the BOOL is typedefed as
typedef int BOOL in a header file

in namespace MyBool
namespace MyBool {
    typedef bool BOOL
    class b : public a
    {
    public:
    bool foo();
    ....
    };
}
when I compile it , the compiler didn't give any error. and when i debug
it, the debugger shows that the second version of foo() overwrites first
version of foo().
but when this two class all defined in global namespace, the compiler
will give a error  that says the two foo() only different in return
type.

Will this kind of define cause some potential bug or it's just works?

Thanks in advance

haitao
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