Bug in tCollection.ForEach? 
Author Message
 Bug in tCollection.ForEach?


Quote:
>In one of my programs I use a collection of collections.
>When I wrote a routine to do some calculations on all items in
>this construction using the standard method FOREACH, my program
>didn't respond as I expected.

This isn't a bug, just a misuse of them.  The documentation isn't clear that
what you're doing is wrong, but it is:

Quote:
>FUNCTION tSecondColl.calcTotal : integer;
>VAR subTotal : integer;
>  PROCEDURE addObject(obj : pMyObject); FAR;
>  BEGIN subTotal := subTotal + obj^.value END;
>  PROCEDURE addFirstColl(coll : pFirstColl); FAR;
>  VAR i : integer;


Here's the problem.  Your addObject procedure is a local procedure, but that's
not enough:  it has to be local to the routine that calls ForEach.  Change
this part of your code as shown and things should be fine:

FUNCTION tSecondColl.calcTotal : integer;
VAR subTotal : integer;

  PROCEDURE addFirstColl(coll : pFirstColl); FAR;
    PROCEDURE addObject(obj : pMyObject); FAR;
    BEGIN subTotal := subTotal + obj^.value END;


(I deleted the declaration of i here because you weren't using it; this really
has nothing to do with the problem.)

Duncan Murdoch



Wed, 18 Jun 1902 08:00:00 GMT  
 
 [ 1 post ] 

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