一段代码的疑问
CATIMfgManufacturingParameters *piParm =NULL;

CATString ClassName2("CATMfgManufacturingParameters");
::CATInstantiateComponent (ClassName2,
CATIMfgManufacturingParameters::ClassId(),
(void**)& piParm);

CATICkeParmFactory_var spFactL(piRootActivity);
if (piParm && !!spFactL)
{
some code here
}

想问问if语句中spFactL的前边的!!是什么意思？双重否定？

[解决办法]
据说!!是为了转换为bool类型。参见：http://stackoverflow.com/questions/248693/double-negation-in-c-code