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c++operator-precedence

Operator precedence - increment versus member access

Consider this:

++iterator->some_value

Will the iterator be forwarded before some_value is accessed?

According to cppreference increment and member access both have the same precedence of 2. Does the order in which they are listed matter? Or is this undefined - compiler specific?

Solution

  • Note that preincrement and postincrement have different precedences, so the code snippet you've posted doesn't quite match the explanatory text you've linked.

    The preincrement operator has a lower precedence than the member access operator, so ++iterator->some_value is the equivalent of ++(iterator->some_value).

    If instead you had iterator->some_value++ where they both had the same precedence, then the left-to-right associativity comes into effect, and it would be processed as (iterator->some_value)++.