Difference between pre-increment and post-increment in a loop?

Question

Is there a difference in ++i and i++ in a for loop? Is it simply a syntax thing?

Answer 1

There is more to ++i and i++ than loops and performance differences. ++i returns a l-value and i++ returns an r-value. Based on this, there are many things you can do to ( ++i ) but not to ( i++ ).

1- It is illegal to take the address of post increment result. Compiler won't even allow you.
2- Only constant references to post increment can exist, i.e., of the form const T&.
3- You cannot apply another post increment or decrement to the result of i++, i.e., there is no such thing as I++++. This would be parsed as ( i ++ ) ++ which is illegal.
4- When overloading pre-/post-increment and decrement operators, programmers are encouraged to define post- increment/decrement operators like:

T& operator ++ ( )
{
   // logical increment
   return *this;
}

const T operator ++ ( int )
{
    T temp( *this );
    ++*this;
    return temp;
}