https://svn.boost.org/trac10/ticket/8315 <h1 class="section" id="GeneralInfo">General Info</h1> <p> OS:: Windows 7 64bit </p> <p> Compiler:: MSVC 10 </p> <h1 class="section" id="TheCode">The Code</h1> <div class="wiki-code"><div class="code"><pre><span class="n">std</span><span class="o">::</span><span class="n">ostringstream</span> <span class="n">out</span><span class="p">;</span> <span class="n">boost</span><span class="o">::</span><span class="n">iostreams</span><span class="o">::</span><span class="n">tee</span><span class="p">(</span><span class="n">out</span><span class="p">);</span> </pre></div></div><h1 class="section" id="CompilerOutputError">Compiler Output / Error</h1> <pre class="wiki">Boost\Boost_1_53\boost/iostreams/tee.hpp(208): error C2440: '&lt;function-style-cast&gt;' : cannot convert from 'const std::ostringstream' to 'boost::iostreams::tee_filter&lt;Device&gt;' with [ Device=std::ostringstream ] No constructor could take the source type, or constructor overload resolution was ambiguous recurse.cpp(14) : see reference to function template instantiation 'boost::iostreams::tee_filter&lt;Device&gt; boost::iostreams::tee&lt;std::ostringstream&gt;(const Sink &amp;)' being compiled with [ Device=std::ostringstream, Sink=std::ostringstream ] </pre><h1 class="section" id="Analysis">Analysis</h1> <p> The parameter is given to the tee function template as a const-reference: </p> <div class="wiki-code"><div class="code"><pre><span class="k">template</span><span class="o">&lt;</span><span class="k">typename</span> <span class="n">Sink</span><span class="o">&gt;</span> <span class="n">tee_filter</span><span class="o">&lt;</span><span class="n">Sink</span><span class="o">&gt;</span> <span class="n">tee</span><span class="p">(</span><span class="k">const</span> <span class="n">Sink</span><span class="o">&amp;</span> <span class="n">snk</span><span class="p">)</span> <span class="p">{</span> <span class="k">return</span> <span class="n">tee_filter</span><span class="o">&lt;</span><span class="n">Sink</span><span class="o">&gt;</span><span class="p">(</span><span class="n">snk</span><span class="p">);</span> <span class="p">}</span> </pre></div></div><p> Quoting the documentation: </p> <blockquote> <p> The function parameter is a non-const reference if Sink is a stream or stream buffer type, and a const reference otherwise. </p> </blockquote> <p> Actually, this really does not apply to the function parameter, but rather to the tee_filter ctor parameter. </p> <p> So, this boils down to passing a const-reference type to a non-const-reference type as an argument. </p> <h1 class="section" id="ProposedSolution">Proposed Solution</h1> <p> Remove the "const" qualifier from the tee function parameter(s). </p> en-us /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/8315 Trac 1.4.3 Steven Watanabe Wed, 20 Mar 2013 15:01:53 GMT https://svn.boost.org/trac10/ticket/8315#comment:2 https://svn.boost.org/trac10/ticket/8315#comment:2 <ul> <li><strong>status</strong> <span class="trac-field-old">new</span> → <span class="trac-field-new">closed</span> </li> <li><strong>resolution</strong> → <span class="trac-field-new">fixed</span> </li> </ul> <p> (In <a class="changeset" href="https://svn.boost.org/trac10/changeset/83505" title="Make tee work correctly for std::streams. Fixes #8315.">[83505]</a>) Make tee work correctly for std::streams. Fixes <a class="closed ticket" href="https://svn.boost.org/trac10/ticket/8315" title="#8315: Bugs: tee function template does not work for std streams (closed: fixed)">#8315</a>. </p> Ticket Daniel James Thu, 16 May 2013 22:10:19 GMT