*** Quoting Francois Piette from a message to Louis Rizzuto ***
LR> I do not understand the often
Dangerous stuff this type casting IMHO. It bypasses 'strong typing' and this
can and does create ahvoc on projects involving many programmers - or even
one programmer like me that works on on project over many man-years. Hmmm,
it sort of reminds of old times where programmers did - ahwm - unusual stuff
to gain job security and drive managers to terrifying heights of dispair.
Did I contribute to that? :) Naw. I am too straight. But I am learning -
remembering - something important here, me thinks.
Um, that was in response to:
LR> I understand this concept of 'safe'.
FP> Typecasting is use to tell the compiler to consider a variable of a
FP> given datatype to be like a variable with another datatype.
FP> For example: A TList object maintain a list of pointer to other
FP> objects. But you need simple integers in this list, not pointers.
FP> Knowing that an integer has the same size as a pointer, you can
FP> typecast the integer to a pointer type when you put the integer into
FP> the list and typecast it back to an integer when you retrieve the
FP> element.
FP> var SomeIntegerVariable : Integer MyList : TList;
FP> begin MyList.Add(PChar(SomeIntegerVariable)); ... ...
FP> SomeIntegerVariable := Integer(MyList.Last); ... end;
Sorry about that, this quoting system is hard to remember and use.
LR> I do not understand the often
LR> used parameter (Sender : TObject) and why it is used in
FP> virtually
LR> every piece of procedure code I have seen thus far. It's
FP> significance
LR> eludes me still.
FP> Every (or nearly) all event handler procedure takes as first
FP> parameter the well known Sender : TObjet. This allow to have the
Thnaks for that help Francois. I will study it.
Regards, -= Lou =-
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