In C++ why can't I write a for() loop like this: for( int i = 1, double i2 = 0;

Question

or, \"Declaring multiple variables in a for loop ist verboten\" ?!

My original code was

 for( int i = 1, int i2 = 1; 
      i2 < mid;
      i++, i         


        

Answer 1

It's actually a limitation of declaration statements:

int i=0, j=0, *k=&i;     // legal
int i=0, double x=0.0;   // illegel

So, basically, the answer to your final question is: (A) & (B) are the same. (C) is different.

As bta points out:

 z = 1,3,4;

is the same as

 z = 1;

However, that is because = has a higher precedence than ,. If it were written as:

 z = (1,3,4);

then that would be the same as:

 z = 4;