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Who is telling here that the variable must count up?

same here.
same stuff for : since o is not defined, it should be : But apparently it doesn't act like that...
You should have posted it in the bug section [/code]

Polo wrote: You should have posted it in the bug section

Mmmm... May be :roll:

Tested on MSX Basic Ver 3.0, and it only writes 0. Just what must be

No, there's no bug, all is fine.

The test is done new at each loop's beginning and the upper-bound, the TO-value, might be a variable, so e.g. something like the following will run 3 times, not just 1:
In your code o is initialized with 0 (because o=o and o is zero if undeclared before) which is smaller or equal to o=0. Then o is increased by one.
The loop returns to the head and again o (now with value = 1) is checked against the variable o (with value = 1), and so the loop's body will start again, after o is increased one more.
....and so on.

So this loop always starts again for the last time

Well, in the code we're not telling the variable should be increased, so it shouldn't, no ?

> For o=o To o
> Debug o
> Next
> Who is telling here that the variable must count up?

Dunno, but this doesn't compile at all under v3.93 beta 3 -- it gives an error.

Strange...
But anyway i think it's a bug, the variable shouldn't grow, but the code should run

Well.
PB, please don't say lies and don't talk nonsenses.

Froggerprogger, in my opinion you aren't right.
Try in C:
For (o=o;o<=o;o++) {}

And in my opinion it is a bug.
Tested with MSX Basic 3.0, BlitzBasic2 (Amiga) and QuickBasic 4.5. and works fine.

Can someone try it with VB, Powerbasic, Blitz ... ?

Mmmm...
Or Froggerprogger is right ? :roll:
Then PB is well done and the other Basic compilers are buggy?

Mmmm... In C:
When for (o=o;o<=o;o++)
the "<=" is just what must do internally a Basic For-Next loop, i think.
So then all is pointing that PB is well done and the others are fake
Is it possible

Thanx a lot, Froggerprogger

> PB, please don't say lies and don't talk nonsenses.

Well, why not see for yourself before you accuse people of being liars!

File:1->error.gif

> Can someone try it with VB, Powerbasic, Blitz ... ?

With Visual Basic 5, it just prints 0 in the debug window, over and over.

PB wrote:> PB, please don't say lies and don't talk nonsenses.

Well, why not see for yourself before you accuse people of being liars!

File:1->error.gif

Sorry PB. My fault
I didn't believe you.
So, there must be something strange. Here it works with 3.93b3, some user lib, or something there?

JaPB is the problem!
Works not with 3.93 beta3 compiler.

> PB. My fault

Sorry that I snapped at you... I had a bad day and that tipped me over the edge.

> Here it works with 3.93b3

I worked it out -- it does compile with the PureBasic editor, but not jaPBe.
That's why it worked for you but not for me (unless you're using jaPBe too?).

Hehehe... IceSoft beat me by 2 minutes with the answer.

Perhaps there are some languages that compile a for-loop in that way, that at the time when the line is processed, the value 'a' is stored in a seperate place so any changes to 'a' inside the loop will not change the loop's TO-value.
But this would make the for-loop less powerful.

Well, in the code we're not telling the variable should be increased, so it shouldn't, no ?

'o' is the countervariable! Why does 'i' count up in "For i=0 to 100" ?

A For-loop (with positive STEP) is processed in this way:
- check the value of the countervariable against the TO-variable's value
- if both are same, or countervariable < TO-variable then increase the countervariable by step

So if countervariable and TO-variable point to the same variable, e.g. 'i' then both are increased, and will always have the same result => endless loop