Hello,
Say I store class instances of various types in a TFPList. All happen to be
descendants of same superclass C and each one has a specific method "text".
When retrieving and writing an element, if they were all direct instances of C,
I would do something like:
element := C(list[index]); // casting back
text := element.text;
I cannot do that, even if elements all are *indirect* instances of C, because
this calls C.text instead of the element's own proper text method. Which is
wrong, indeed.
So, I must cast elements back to their own type; but I have no idea how to do
this. Doesn't the compiler store this information? After all, when an element
is put into the list, its type is known. Is there a reason why retrieving an
element does not cast it back to its original type automatically? Should I
store element types manually in a parallel list?
There must be a way to solve this issue, I guess...
Side-question: it seems, when subclassing, that methods with same name and same
parameters do not need any modifier keyword (such as "override" or "overload").
Eg I can have
function text;
in both a superclass C0 and a subclass C1 work as expected. Correct?
Thank you,
Denis
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