Confusion about C++ iterator dereferencing code

Question

I am looking at the following line of code

++ptr_it->refcount;

where ptr_it is an iterator for a list of a particular class where refcount is an integer member variable. I can't figure out whether the ++ operator here is being used to go to the next element of the list in the ptr_it or if it is being used to increment the refcount variable. Or maybe both? I figure that refcount must be affected in some way otherwise I'm not sure why it is dereferenced here. Can anyone tell me what is actually happening here.

Can’t you try it and debug it and see value before and after? — Andrew Truckle, Aug 18 '19 at 18:01
https://en.cppreference.com/w/cpp/language/operator_precedence — Mat, Aug 18 '19 at 18:03

score 0 · Answer 1 · answered Aug 18 '19 at 18:02

0

In the statement

++ptr_it->refcount;

the variable being incremented is refcount. There's no ambiguity and no way that more than one thing would be incremented.

answered Aug 18 '19 at 18:02

Jesper Juhl

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Confusion about C++ iterator dereferencing code

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