C++ Syntax: Increment: ++


Possibly the most well known operator in C++; ++ is a unary operator that can be applied to variables and increments the value they hold. For example often for loops have, as their increment-expr something like:-
that just adds one to counter.

Like all other C++ operators, ++ returns a value:-

  1. If ++ precedes the variable, e.g. ++counter, the value returned is the value in counter after it has been incremented.
  2. If ++ follows the variable, e.g. counter++, the value returned is the value in counter before it has been incremented.
This allows some C++ pedants to say that C++ is wrong, as it implies the enhanced value isn't used, and that it should be called ++C. Those who are less keen on C++ argue that the name is right for the same reasons!

See operator precedence

Other Uses for ++

None, although it might appear that there is a possible confusion with the arithmetic + operator followed a unary +. However C++ applies the rule that it always takes the longest legal operator sequence, so ++ is interpreted as the increment operator.

Usage Notes

Its best not to overuse the operator, and never apply it twice to the same variable in the same statement, for example:-
my_int[index++] = index++;
is ambiguous as C++ is allowed to evaluate either ++ first. Remember KISS = Keep It Simple Stupid!
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