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ick. . . i hate weird compilers

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01000101
ok, so i use DEV/C++ on my windoze box, and i compile a program with the lines

Code:
for (i=0;i<100;i+2)
{ statements }


and it compiles nicley on DEV, and "i" now adds in incriments of two..
but if i compile with the SAME EXACT code on VC++ of my unix gcc/g++... then i get errors saying that the "i"+2 needs to be "i"++ , which i understand, but i dont want it to be i++, i want it to be i+2, or i+++... can someone tell me how to do the same thing with the for loop in VC++?
AftershockVibe
Convert it to a while loop instead of using FOR. Syntax may not be exact as I don't know the language...

Code:

i=0;
while(i<100)
{
statements
i = i + 2;
}
01000101
thnx, i thought there might be another way to get around the oversensitive compiler of VC++, but the do/while loop does the same functioning..

Pe@cE
Liu
You can attempt i++++;
Kaneda
The C for-loop has always seemed to be a strange beast, since it's almost too versatile... The actual definition is:

Code:
for (expression; expression; expression) statement


... but most people I know of think of it as:

Code:
for (statement; expression; statement) statement


... or even more specifically:

Code:
for (initializer; condition; incrementer) statement


All those definitions hold because most (if not all) statements in C are also expressions. "y = 2;" equals 2 for example, which is why you can do "x = y = 2;".

Your code actually only fits with the first definition, and in reality, if it worked, it would be pretty useless. More specifically, it would cause an infinite loop. Because you never actually change the value of i. But it should, as far as I'm aware be valid code, even if most compilers (sensibly) won't allow it.

"i+2" isn't an incrementer, it's not a statement either, it's an expression yielding "i plus 2", but not assigning or using that value anywhere.

The short version: I think you'd want to use:

Code:
for (i = 0; i < 100; i += 2)


Note the "+=" replacing the "+" Wink
Liu
Kaneda wrote:

Code:
for (i = 0; i < 100; i += 2)


Note the "+=" replacing the "+" Wink

We have a winner.
01000101
Magnificent. Thank you a ton, i can see why the compiler would have conflicting interests in this case.. i still want to know why my DEV/C++ compiler worked like a charm with the origional statement, maybe it has some sort of safeguard for those things.

thanks again.
im going to close this topic down because its no longer needed.

Pe@cE
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