[Boost-users] Re: Converting from const to non-const withiterator_adaptor

7 Jan 2004

      ...
I was quoting the same documentation you referred to.
OK, but my quote came from the front page (index.html), so I read that
first.  Perhaps that section should be rewritten.
...
I'd love to.  If I'm to use your code wholesale, I'll need you to
add the standard boost copyright and license reference.
I've done that, and attach the new source.  However, I hereby relinquish all
rights over baz2.cpp, so feel free to do whatever you like with it.

When I attempted to integrate the iterators with my actual code, I hit a
problem that I don't know how to resolve with iterator_facade.  To
illustrate it, I've modified the example code and attach it as baz3.cpp.
Now, Node is an abstract base class, and DerivedNode is instantiated.
Compiling it results in the following error:

\CVS\boost\boost\iterator\iterator_facade.hpp(389) : error C2259:
'Node' : cannot instantiate abstract class due to following members:
'int Node::getInfo(void) const' : pure virtual function was not defined

Can your technique be used in such contexts?

Thanks,
Keith MacDonald

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