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cpointersstructureoperator-precedence

What is the order of evaluation in below code written in C?

a is a pointer to structure and b is the structure

a++ -> b

The order of evalution of above code will be 

((a++) -> b)

or 

(a -> b) ++
Solution

  • As postfix increment and the pointer to member operator have exactly the same precedence, the associativity of the two operators comes into play. Both are left to right.

    Hence 

    a++ -> b

    is evaluated as

    (a++) -> b

    This means that the -> applies to the previous value of the pointer a, and a is incremented with the normal rules - to be accomplished sometime before the statement completes execution.

    (One for the pub quiz, the prefix increment has a lower precedence than ->).