Hi All,<div><br></div><div>I&#39;m trying to do some slightly hooky stuff with the iterators library and cannot get the following code to compile.</div><div><br></div><div>When the second last line of main is uncommented (&quot;ZIter iter(b);&quot;), compilation fails.</div>
<div><br></div><div>The error mesages suggest this is a problem with determining the appropriate traversal category of &quot;ZIter&quot;.</div><div><br></div><div>Can anyone advise if this is problem with my code, a bug, am I asking too much of the library, ...?</div>
<div><br></div><div>Cheers,</div><div>Simon Knapp.</div><div><br></div><div><div>compiler:</div><div>Visual Studio 2008 - version 9.0.30729.1 SP</div></div><div><br></div><div><br></div><div>//----------------------------------------------------------------------------------------------------------------------------</div>
<div>// begin iterator_tests.cpp</div><div>//----------------------------------------------------------------------------------------------------------------------------</div><div><div>#include &lt;vector&gt;</div><div><br>
</div><div>#include &lt;boost/iterator/filter_iterator.hpp&gt;</div><div>#include &lt;boost/iterator/zip_iterator.hpp&gt;</div><div>#include &lt;boost/tuple/tuple.hpp&gt;</div><div><br></div><div>typedef std::vector&lt;long long&gt; LLGrid;</div>
<div>typedef std::vector&lt;float&gt; FloatGrid;</div><div><br></div><div>typedef LLGrid::const_iterator LLGridIter;</div><div>typedef FloatGrid::const_iterator FloatGridIter;</div><div><br></div><div>typedef boost::tuples::tuple&lt;LLGridIter, FloatGridIter&gt; IDAndAreaTuple;</div>
<div>typedef boost::zip_iterator&lt;IDAndAreaTuple&gt; IDAndAreaIterator;</div><div>typedef std::iterator_traits&lt;IDAndAreaIterator&gt;::reference IDAndAreaRef;</div><div><br></div><div>struct Fnctr {</div><div>    bool operator()(const IDAndAreaRef ref) const {</div>
<div>        return true;</div><div>    }</div><div>};</div><div><br></div><div>typedef boost::filter_iterator&lt;Fnctr, IDAndAreaIterator&gt; FIter;</div><div>typedef boost::tuples::tuple&lt;FloatGridIter, FIter&gt; ZIterTuple;</div>
<div>typedef boost::zip_iterator&lt;ZIterTuple&gt; ZIter;</div><div><br></div><div>static ZIterTuple makeZIterTuple(</div><div>    Fnctr const&amp; fnctr,</div><div>    LLGridIter const&amp; beginIdGrid,</div><div>    LLGridIter const&amp; endIdGrid,</div>
<div>    FloatGridIter const&amp; beginAreaGrid,</div><div>    FloatGridIter const&amp; endAreaGrid,</div><div>    FloatGridIter const&amp; gtgdIter</div><div>    ) {</div><div>    return</div><div>        boost::make_tuple(</div>
<div>            gtgdIter, </div><div>            boost::make_filter_iterator(</div><div>                fnctr,</div><div>                boost::make_zip_iterator(boost::make_tuple(beginIdGrid, beginAreaGrid)),</div><div>
                boost::make_zip_iterator(boost::make_tuple(endIdGrid, endAreaGrid))</div><div>            )</div><div>        );</div><div>}</div><div><br></div><div>int main(int argc, char* argv[]) {</div><div>    FloatGrid areaMask, regionStat;</div>
<div>    LLGrid regionMask;</div><div>    ZIterTuple b(makeZIterTuple(Fnctr(), regionMask.begin(), regionMask.end(), areaMask.begin(), areaMask.end(), regionStat.begin()));</div><div>    //ZIter iter(b);</div><div>    return 0;</div>
<div>}</div></div><div><div>//----------------------------------------------------------------------------------------------------------------------------</div><div>// end iterator_tests.cpp</div><div>//----------------------------------------------------------------------------------------------------------------------------</div>
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