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Simple question (namespaces and operators)

 
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Marco T.
Guest
PostPosted: Wed Aug 09, 2006 9:10 am    Post subject: Simple question (namespaces and operators) Reply with quote


Hi all,

why the former code fragment works and the latter doesn't?

=============
//CORRECT CODE:

namespace ciao
{
class A{};
A operator *(A &a, A &b) {return a;};
A method() ;
}
using namespace ciao;
A method() {A a1,a2; return a1*a2;}
=============
//INCORRECT CODE

namespace ciao
{
class A{};
A operator *(A &a, A &b);
A method() ;
}
using namespace ciao;
A operator *(A &a, A &b) {return a;}
A method() {A a1,a2; return a1*a2;} //line X

error: 'operator *' is ambiguous at line X
(compiler: VC++ 6.0)

=============
The issue is that I don't want to write the implementation of operator
* inside the namespace declaration.

thanks
marco
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Marco T.
Guest
PostPosted: Wed Aug 09, 2006 9:10 am    Post subject: Re: Simple question (namespaces and operators) Reply with quote


Sumit RAJAN wrote:

Quote:
A ciao::operator *(A &a, A &b) {return a;}

I would not recommend the using directive. Further, it may be a nice
idea to make the parameters const refs.

A method() {A a1,a2; return a1*a2;} //line X

Regards,
Sumit.

Thanks!

:-)
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Sumit RAJAN
Guest
PostPosted: Wed Aug 09, 2006 9:10 am    Post subject: Re: Simple question (namespaces and operators) Reply with quote


Marco T. wrote:

Quote:
//INCORRECT CODE

namespace ciao
{
class A{};
A operator *(A &a, A &b);
A method() ;
}
using namespace ciao;
A operator *(A &a, A &b) {return a;}

A ciao::operator *(A &a, A &b) {return a;}

I would not recommend the using directive. Further, it may be a nice
idea to make the parameters const refs.

Quote:
A method() {A a1,a2; return a1*a2;} //line X

Regards,
Sumit.
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