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

From: Keith MacDonald (boost_at_[hidden])
Date: 2004-01-07 07:19:00

> 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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