Dave Carrigan wrote:
>
> Yes, and this technique is also very useful for implementing a typesafe
> C++ GetObjectPtr function.
>
> template <class T>
> inline T* GetObjectPtr(FormType* frm, const UInt16 item)
> {
> return static_cast<T*>(FrmGetObjectPtr(frm, FrmGetObjectIndex(frm,
> item)));
> }
I'd only consider this to be safe if it checked for the correct object
kind:
template <typename T>
void GetObjectPtr(T * &result,
UInt16 index,
FormType *frmP = FrmGetActiveForm())
{
ErrFatalDisplayIf(FrmGetObjectType(frmP,index)!=traits<T>::kind,
"Invalid Form object cast attempted!");
return static_cast<T *>(FrmGetObjectPtr(frmP,index));
}
with traits specializations for all appropriate types.
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