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    <p>What bridges do you need? </p> <p>You can use all the Qt container classes with std algorithms. Most of the time I prefer the Qt container classes because I'm sure they use the copy-on-write idiom (constant time operation). Qt's foreach function creates a copy of the container so its nice that you know for sure it is a constant time operation. </p> <p>If the Qt signal slot mechanism is to slow you can switch to the boost alternative. The great thing about Qt signal/slot is the signal/slot connection between two threads.</p> <p>QtConcurrent works great with BOOST.Lambda</p> <hr> <p>For "shared" child-parent relationship I use this helper function.</p> <pre><code>template &lt;class Object&gt; static boost::shared_ptr&lt;Object&gt; makeSharedObject() { using namespace boost; using namespace boost::lambda; return boost::shared_ptr&lt;Object&gt;( new Object(), bind( &amp;Object::deleteLater, _1 ) ); } </code></pre> <hr> <p>Qt containers are not supported by Boost.serialize, you'll have to write the serialize functions yourself. I would love a bridge between the Qt streaming classes and Boost.archive.</p> <p>Here is my QList serialization template you can figure out the rest of them ...</p> <pre><code>///\file document is based on "boost/serialization/list.hpp" namespace boost { namespace serialization { //--------------------------------------------------------------------------- /// Saves a QList object to a collection template&lt;class Archive, class U &gt; inline void save(Archive &amp;ar, const QList&lt; U &gt; &amp;t, const uint /* file_version */ ) { boost::serialization::stl::save_collection&lt; Archive, QList&lt;U&gt; &gt;(ar, t); } //--------------------------------------------------------------------------- /// Loads a QList object from a collection template&lt;class Archive, class U&gt; inline void load(Archive &amp;ar, QList&lt;U &gt; &amp;t, const uint /* file_version */ ) { boost::serialization::stl::load_collection&lt; Archive, QList&lt;U&gt;, boost::serialization::stl::archive_input_seq&lt;Archive, QList&lt;U&gt; &gt;, boost::serialization::stl::no_reserve_imp&lt; QList&lt;U&gt; &gt; &gt;(ar, t); } //--------------------------------------------------------------------------- /// split non-intrusive serialization function member into separate /// non intrusive save/load member functions template&lt;class Archive, class U &gt; inline void serialize(Archive &amp;ar, QList&lt;U&gt; &amp;t, const uint file_version ) { boost::serialization::split_free( ar, t, file_version); } } // namespace serialization } // namespace boost BOOST_SERIALIZATION_COLLECTION_TRAITS(QList) </code></pre> <hr> <p>If you want Boost.Bind to handle QPointer as a normal pointer (like shared_ptr):</p> <pre><code>namespace boost { template&lt;typename T&gt; T * get_pointer(QPointer&lt;T&gt; const&amp; qPointer) { return qPointer; } } </code></pre> <hr> <p>Using <code>QIODevice</code> where a <code>std::stream</code> is needed</p> <pre><code>namespace boost { namespace iostreams { class IoDeviceSource { public: typedef char char_type; typedef source_tag category; explicit IoDeviceSource(QIODevice&amp; source) : m_source(source) { } std::streamsize read(char* buffer, std::streamsize n) { return return m_source.read(buffer, n); } private: QIODevice&amp; m_source; }; class IoDeviceSink { public: typedef char char_type; typedef sink_tag category; explicit IoDeviceSink(QIODevice&amp; sink) : m_sink(sink) { } std::streamsize write(const char_type* buffer, std::streamsize n) { return m_sink.write(buffer, n); } private: QIODevice &amp;m_sink; }; class IoDeviceDevice { public: typedef char char_type; typedef seekable_device_tag category; explicit IoDeviceDevice(QIODevice&amp; device) :m_device(device) { } std::streamsize write(const char_type *buffer, std::streamsize n) { return m_device.write(buffer, n); } std::streamsize read(char* buffer, std::streamsize n) { return m_device.read(buffer, n); } stream_offset seek(stream_offset off, std::ios_base::seekdir way) { using namespace std; stream_offset next(0); if(way==ios_base::beg) { next = m_device.pos(); } else if(way==ios_base::cur) { next = m_device.pos() + offset; } else if(way==ios_base::end) { next = m_device.size() -1 + offset; } else { throw ios_base::failure("bad seek direction"); } if( !m_device.seek(next) ) { throw ios_base::failure("bad seek offset"); } return m_device.pos(); } private: QIODevice &amp;m_device; }; } } </code></pre> <p><strong>Example</strong></p> <pre><code>#include &lt;iostream&gt; #include &lt;QFile&gt; #include &lt;boost/iostreams/stream.hpp&gt; #include "iodevicestream.h" int main(int argc, char *argv[]) { namespace io = boost::iostreams; QVector&lt;int&gt; data; QFile fl("temp.bin"); fl.open(QIODevice::ReadWrite); io::stream&lt;io::IoDeviceDevice&gt; inoutput( fl ); std::copy(data.begin(), data.end(), std::ostream_iterator&lt;int&gt;(inoutput, "\n")); inoutput.flush(); inoutput.seekg(0, std::ios_base::beg); std::cout &lt;&lt; inoutput; return 0; } </code></pre>
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    1. CO@TimW That's the best answer so far... Thanks for real-world code. Knowing how popular Boost is I hope Qt team will make these kind of bridges part of the framework to save people from reinventing the wheel. I think that would also help in faster adoption of Qt among developers working with Boost already. This may be seen as a very important factor of Qt's popularity in certain C++ circles.
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      1. USPiotr Dobrogost
    2. COShouldn't the case with `way==ios_base::beg` in `seek` set `next` to `offset` rather than `m_device.pos()`?
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      1. USAdam Badura
 

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