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POOperator overloading and iterator confusion
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  1. POOperator overloading and iterator confusion
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    copied!<p>I use this code to find the point of a box (<code>g</code>) furthest in the direction <code>d</code> typedef vector_t point_t;</p> <pre><code>std::vector&lt;point_t&gt; corners = g.getAllCorners(); coordinate_type last_val = 0; std::vector&lt;point_t&gt;::const_iterator it = corners.begin(); point_t last_max = *it; do { coordinate_type new_val = dot_product( *it, d ); if( new_val &gt; last_val ) { last_val = new_val; last_max = *it; } } while( it != corners.end() ); return last_max; </code></pre> <p>I also have a template operator overload for the operator <code>!=</code> for the class <code>vector_t</code> which is in the namespace <code>point</code>.</p> <pre><code>namespace point { template &lt; typename lhs_vector3d_impl, typename rhs_vector3d_impl &gt; bool operator!=( const typename lhs_vector3d_impl&amp; lhs, const typename rhs_vector3d_impl&amp; rhs ) { return binary_operator_not_equal&lt;lhs_vector3d_impl, rhs_vector3d_impl&gt;::apply( lhs, rhs ); } }; </code></pre> <p>The overload works fine in most cases but when I use with iterators (i.e. <code>it != corners.end()</code>) it breaks down since I did not intend this function in that case. I can tell it's because of the template parameters resolution going wrong but i don't know why:</p> <pre><code>lhs_vector3d_impl=std::_Vector_const_iterator&lt;std::_Vector_val&lt;std::_Simple_types&lt;legend::geometry::point::Carray_Vector3d&lt;int32_t&gt;&gt;&gt;&gt;, rhs_vector3d_impl=std::_Vector_iterator&lt;std::_Vector_val&lt;std::_Simple_types&lt;legend::geometry::point::Carray_Vector3d&lt;int32_t&gt;&gt;&gt;&gt; </code></pre> <p>I understand the wrong functions get called but I don’t understand why…</p> <p>So basically my question is how comme iterator comparaison gets resolved with my function instead of an operator in the std namespace and how can I prevent this function from being used.</p> <p>Note 1: I am beginning with template so I may be doing something very wrong without knowing, if so please kindly tell.</p> <p>Note 2: this code is used mainly for academic purposes so I really want to do most of it by hand.</p> <p>Note 3: using Visual Studio 2012 C++ compiler</p>
 

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