Willy Wood <ofile@aquanet.co.il> writes:
 ...
>The following is a declaration of a set of pointers to class X.
> Who can tell me why it contains an almost impossible
>to detect bug ?

>#include <set.h>

>class X
>{
>};

>typedef set<X*,less<X*> > setX;

You are allowed to compare two pointers (in either C, or C++) only
if they point within the same array.  Your setX will work if, and
only if, it is only every instantiated with members which all point
into the same array, since using "less<X*>" implies using operator<()
to compare pointers to X.


Alex
--
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The following is a declaration of a set of pointers to class X.
 Who can tell me why it contains an almost impossible
to detect bug ?

#include <set.h>

class X
{
};

typedef set<X*,less<X*> > setX;


--
Willy Wood, Israel.



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