FinalValue recalculation in FOR-loop

[Vittorio]

Hi there,
Sorry for the stupid question 
I've got such a loop and want to recalculate finalValue = TreeView1.Items.Count-1 after each cycle.

Code: Pascal  [Select][+][-]

1. for i := 0 to TreeView1.Items.Count-1 do
2. begin
3.   //TreeView1.Items.Count can be increased
4. end;
5.  

Is it possible?

[Bart]

Use a while or repeat loop.
The end condition in a for loop is evaluated only once: when entering the loop.
This is by design and has been so always.

Bart

[Thaddy]

No. a for to loop is fixed to the initial values.
You can use repeat until or while, though, if the count must change
[edit posts crossed Bart. Basically same answer]

Note actually this can be done, but it involves pointer trickery and not recommended.
E.g. bad code:

Code: Pascal  [Select][+][-]

1. {$mode delphi}{$H+}
2. var
3.   i:integer;
4.   k:integer = 10;
5. begin
6.   for i := 0 to 10 do
7.   begin
8.    writeln(k);
9.    inc(Pinteger(@k)^);
10.    if k >= 20 then exit;
11.   end;
12. end.

Never do that!!!
(but it works  Partially )

[Vittorio]

Thank you very much!