asked on

Reference to no object does not produce any run time error (MSVS2010 C++)

//my program wants to get a reference to an orange.
orange& myOrangeRef=theApp.findOrangeByID(id); //no oranges yet
myOrangeRef.someFunc();//succeeds, but WHY? //No object exists why does call succeed

CODE
//caller
orange& myOrangeRef=theApp.findOrangeByID(id);

//called function
orange& CProject2App::findOrangeByID(integer id)
{
.....
.....
return *pOrange; //pOrange is NULL, no error in CALLEE
}

ASKER CERTIFIED SOLUTION

ambience

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SOLUTION

phoffric

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phoffric

typo - Should be " or, it is not referring to any orange class data member.
(looks like I was typing while ambience was submitting)

phoffric

Although this is the first time I've seen a reference having a NULL value, (so I'm guessing this isn't standard or good practice), if you actually did have a need to pass this exceptional NULL case using your constructs, then the caller needs to test for this condition, as follows:

if( &myOrangeRef == NULL ) {
// Handle the exceptional NULL case condition here
}
else {
// normal processing here
}

supportoranges

ASKER

Thanks for contributing -- I feel like I know so much more about references now!

supportoranges

ASKER

You are both right - I never accessed data members so it never crashed and I will redesign my construct. Thank you.