Re: [boost] [graph] [iterator] use of iterator_facade in leda_graph.hpp

From: David Abrahams (dave_at_[hidden])
Date: 2007-03-15 17:09:03

on Sat Mar 10 2007, Jens Müller <jens.mueller-AT-ira.uka.de> wrote:

> Thomas Witt schrieb:
>> Jens Müller wrote:
>>>  From leda_graph.hpp:
>>>
>>> class out_edge_iterator
>>>        : public iterator_facade<out_edge_iterator,
>>>                                 leda::edge,
>>>                                 bidirectional_traversal_tag,
>>>                                 const leda::edge&,
>>>                                 const leda::edge*>
>>>
>>> Can someone explain to me the parameter "const leda::edge*"?
>> 
>> I can't explain it to you, but it looks suspiciously as if the author meant
>> 
>> class out_edge_iterator
>>    : public iterator_facade<
>>                 out_edge_iterator
>>               , leda::edge const
>>               , bidirectional_traversal_tag>
>
> If I make these change (for all n occurences of the above), my program
> using leda_graph.hpp still works fine ...

Then I'm betting you didn't have very complete tests for your original
iterator.  Did you try running it through the appropriate concept
checks

  boost::function_requires<
    boost_concepts::BidirectionalIteratorConcept<out_edge_iterator> >();

for example?

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com