doubt with this qt's code

[Gopala Krishna]

When I was going through source of qt4.2 I was just pulled by the implementation of 'foreach' esp for compilers without typeof method.
But I just couldn't understand as to why ternary operators are used when 0 could have been used directly. Am I missing something ? Can someone enlighten me ?

#define Q_FOREACH(variable, container) \
    for (const QForeachContainerBase &_container_ = qForeachContainerNew(container); \
         qForeachContainer(&_container_, true ? 0 : qForeachPointer(container))->condition();       \
         ++qForeachContainer(&_container_, true ? 0 : qForeachPointer(container))->i)               \
        for (variable = *qForeachContainer(&_container_, true ? 0 : qForeachPointer(container))->i; \
             qForeachContainer(&_container_, true ? 0 : qForeachPointer(container))->brk;           \
             --qForeachContainer(&_container_, true ? 0 : qForeachPointer(container))->brk)
 
#endif

#define Q_FOREACH(variable, container) \
    for (const QForeachContainerBase &_container_ = qForeachContainerNew(container); \
         qForeachContainer(&_container_, true ? 0 : qForeachPointer(container))->condition();       \
         ++qForeachContainer(&_container_, true ? 0 : qForeachPointer(container))->i)               \
        for (variable = *qForeachContainer(&_container_, true ? 0 : qForeachPointer(container))->i; \
             qForeachContainer(&_container_, true ? 0 : qForeachPointer(container))->brk;           \
             --qForeachContainer(&_container_, true ? 0 : qForeachPointer(container))->brk)

#endif

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[wysota]

Because the operator casts the result to the result returned by qForeachPointer() even though it returns 0 (because of the "true" condition).