Re: Undefined reference to...
* Andrea Crotti, on 11.11.2010 17:54:
"Alf P. Steinbach /Usenet"<alf.p.steinbach+usenet@gmail.com> writes:
Sorry, the simplest way and the practical way to support multiple
instances is to expose class Extended to the client code.
Cheers& hth.,
- Alf
I didn't get this sentence, what could be the alternative?
I also tried to include the son class in the header and in the .cpp file
but it still doesn't really work...
at the moment the code is something like:
auto_ptr<Packet> Packet::parseStream(const Stream& st)
{
Stream tmp = st;
auto_ptr<Packet> res;
FieldHeader fh(tmp.trim(FieldHeader::HEADER_SIZE));
switch (fh.type) {
case BEACON:
res.reset(new Beacon);
*res = Beacon::parseStream(tmp);
break;
}
return res;
}
that reset maybe can be written in another way but for the rest I think
it works well.
The above changes the context of the discussion.
The context of my remark was the earlier discussion, where there was a virtual
member function 'getLower' with no arguments, producing a result of a fixed (but
to client code unknown) type.
In your new context you have a virtual member function 'parseStream' that
produces a result of a type depending on the contents of a stream, i.e. not a
fixed type.
Don't expect an answer to a question A to necessarily apply to a in your view
"similar" question B.
Repeat: readers are not mind-readers.
Cheers & hth.,
- Alf
--
blog at <url: http://alfps.wordpress.com>