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    <p>The original poster failed to actually post the code that was causing the problem.</p> <p>He has since edited my post with the correct code that demonstrates the problem. The code that demonstrates the problem follows:</p> <pre><code>template &lt;class R, typename B=int&gt; class AVectorContainer { public: AVectorContainer() {} typedef R* ptr_Type; typedef const B &amp; const_ref_Type; typedef std::pair&lt;const_ref_Type ,ptr_Type&gt; entry; void insert(ptr_Type aPointer, const_ref_Type aID) { entry aEntry=std::make_pair(aID,aPointer); mVector.push_back(aEntry); } private: std::vector&lt;entry&gt; mVector; }; class SomeType { public: SomeType(){ x=5; } ~SomeType(){ } int x; }; int main() { SomeType * aTipe= new SomeType; int aID=1; AVectorContainer&lt;SomeType&gt; aContainer; aContainer.insert(aTipe,aID); return 0; } </code></pre> <p>Compiler output:</p> <pre><code>/usr/include/c++/4.7/bits/stl_pair.h:88: error: non-static reference member 'const int&amp; std::pair&lt;const int&amp;, SomeType*&gt;::first', can't use default assignment operator </code></pre> <p>The flaw is in these lines:</p> <pre><code> typedef R* ptr_Type; typedef const B &amp; const_ref_Type; typedef std::pair&lt;const_ref_Type ,ptr_Type&gt; entry; std::vector&lt;entry&gt; mVector; </code></pre> <p>Here, the original poster attempts to make a <code>vector</code> of <code>pair</code>s that contain a constant reference, and then does this:</p> <pre><code>entry aEntry; aEntry=std::make_pair(aID,aPointer ) </code></pre> <p>this attempts to assign one pair to another. But <code>const&amp;</code> variables cannot be assigned to another -- they can be constructed (initialized) from another <code>const&amp;</code>, but not assigned.</p> <p>An easy fix is:</p> <pre><code>entry aEntry=std::make_pair(aID,aPointer ) </code></pre> <p>so that we are not constructing <code>aEntry</code> from another <code>entry</code>, instead of default constructing <code>aEntry</code> (which is also illegal: <code>const&amp;</code> must be initialized), then assigning to it.</p>
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    1. POstd::vector inserting std::pair
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    1. USYakk - Adam Nevraumont
    1. USYakk - Adam Nevraumont
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    1. POstd::vector inserting std::pair
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    1. COTrue, I didn't pay much attention to the actual code. I was too busy `SnD'ing` the typos!
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    2. COseriously?? this is a solution?? just checking the types and adding some class that was just writting for showing proposing?.
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    3. CO@Ricardo_arg it wasn't much of a question. Your code was full of typos -- TheOtherGuy fixed that. I noticed you also had a pile of unnecessary `new`s: rather than editing TheOtherGuy's answer to remove them, I tossed it out here. If ThatOtherGuy improved his answer, I'd just delete mine.
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