extending the above example
Base B;
DerivedClasses D1, D2;
B's content -> {content_of_B }
D1's content -> { content_of_B, <D1_specific_data_and_functions>}
D2's content -> { content_of_B, <D2_specific_data_and_functions>}
Can you see the reason now? The above is a very simplified example, think of
virtual classes too :).
Programmers should realize their critical importance and responsibility in a
world gone digital. They are in many ways similar to the priests and monks
of Europe's Dark Ages; they are the only ones with the training and insight
to read and interpret the "scripture" of this age.
On Thu, Jan 20, 2011 at 10:21 PM, yq Zhang <[email protected]> wrote:
> The reason is simple. The same thing happen in other language such as JAVA.
> You can convert Derived class to Base class but you can't convert Derived[]
> to Base[]. The reason is, if your Base class has two derived classes D1, D2.
> They can exist in Base[] because D1, D2 are valid Base instances. While you
> doing converting from Base[] to D1[], it's not possible, because in Base
> there are other D2 instances. To avoid these common mistakes, converting
> from Derived[] to Base[] it not allowed.
>
> Yq
>
>
> On Thu, Jan 20, 2011 at 5:54 AM, Decipher <[email protected]> wrote:
>
>> When we can convert Derived* to Base* then why can't we convert Derived**
>> to Base** ??
>>
>> --
>> You received this message because you are subscribed to the Google Groups
>> "Algorithm Geeks" group.
>> To post to this group, send email to [email protected].
>> To unsubscribe from this group, send email to
>> [email protected]<algogeeks%[email protected]>
>> .
>> For more options, visit this group at
>> http://groups.google.com/group/algogeeks?hl=en.
>>
>
> --
> You received this message because you are subscribed to the Google Groups
> "Algorithm Geeks" group.
> To post to this group, send email to [email protected].
> To unsubscribe from this group, send email to
> [email protected]<algogeeks%[email protected]>
> .
> For more options, visit this group at
> http://groups.google.com/group/algogeeks?hl=en.
>
--
You received this message because you are subscribed to the Google Groups
"Algorithm Geeks" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/algogeeks?hl=en.
