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    <p>After consulting with comp.lang.c++.moderated I came up with the code detailed below. The <code>PushBack()</code> macro is used to add new items to the list, one can iterate through the items by using the <code>Next()</code> macro, and the last item can be recognized from that its 'next item' is itself. So a very basic example code: </p> <pre><code>struct A {}; namespace NS1 { struct B {}; struct C {}; struct D {}; // building up the compile-time list struct Head; PushBack(Head, A); PushBack(Head, B); } PushBack(NS1::Head, NS1::C); namespace NS1 { PushBack(Head, D); } // iterate through the list namespace NS2 { // end of the list reached (recognized from PrevItem == Item) template &lt;class ListId, class Item&gt; void print(Wrapper&lt;Item&gt;, Wrapper&lt;Item&gt;) {} // process Item and advance to the next element template &lt;class ListId, class PrevItem, class Item&gt; void print(Wrapper&lt;PrevItem&gt;, Wrapper&lt;Item&gt;) { cout &lt;&lt; typeid(Item).name() &lt;&lt; endl; print&lt;ListId&gt;(Wrapper&lt;Item&gt;(), Wrapper&lt; Next(ListId, Item) &gt;()); } } </code></pre> <p>A more detailed example that also contains an iterator to ease the use of the list can be found <a href="http://ideone.com/UNDDA" rel="nofollow">here</a> or <a href="http://dl.dropbox.com/u/3095355/CompileTimeList.cpp" rel="nofollow">here</a>. </p> <p>The most important part of the 'library':</p> <pre><code>/// Helper class to wrap incomplete types and avoid instantiation of T template&lt;class T&gt; struct Wrapper {}; namespace CTList { /// The front of compile-time lists struct Nil {}; } /// Compile-time list helper template&lt; typename ListId, typename Item &gt; Item NextInListHelper( ::Wrapper&lt;ListId&gt;, ::Wrapper&lt;Item&gt; ); /// The last element of the list #define Back(ListId) \ decltype( NextInListHelper( ::Wrapper&lt;ListId&gt;(), ::Wrapper&lt;\ decltype( NextInListHelper( ::Wrapper&lt;ListId&gt;(), ::Wrapper&lt;\ decltype( NextInListHelper( ::Wrapper&lt;ListId&gt;(), ::Wrapper&lt;\ decltype( NextInListHelper( ::Wrapper&lt;ListId&gt;(), ::Wrapper&lt;\ decltype( NextInListHelper( ::Wrapper&lt;ListId&gt;(), ::Wrapper&lt;\ decltype( NextInListHelper( ::Wrapper&lt;ListId&gt;(), ::Wrapper&lt;\ decltype( NextInListHelper( ::Wrapper&lt;ListId&gt;(), ::Wrapper&lt;\ decltype( NextInListHelper( ::Wrapper&lt;ListId&gt;(), ::Wrapper&lt;\ decltype( NextInListHelper( ::Wrapper&lt;ListId&gt;(), ::Wrapper&lt;\ decltype( NextInListHelper( ::Wrapper&lt;ListId&gt;(), ::Wrapper&lt;\ CTList::Nil \ &gt;())) \ &gt;())) \ &gt;())) \ &gt;())) \ &gt;())) \ &gt;())) \ &gt;())) \ &gt;())) \ &gt;())) \ &gt;())) /// Add a new element (type) to the list #define PushBack( ListId, item) \ item NextInListHelper( ::Wrapper&lt; ListId &gt;, ::Wrapper&lt; Back(ListId) &gt; ) /// The next element in the ('ListId') list after 'item' #define Next(ListId, item) decltype(NextInListHelper(::Wrapper&lt;ListId&gt;(), ::Wrapper&lt;item&gt;() )) </code></pre> <p>It uses <code>NextInListHelper</code> function declarations and Argument Dependent (Name)Look-up to record the list. The last element of the list can be referenced using the <code>Back</code> macro.</p> <p>The first element of the list can be accessed as: <code>Next(ListId, CTList::Nil)</code>, the last element of the list can be recognized from that it is the same as its next element (<code>LastItem == Next(ListId, LastItem)</code>). </p> <p>I tested it only with gcc 4.6.3, but it is intended to be fully C++11 compliant. </p> <p>A few words about the solution:</p> <ul> <li>in this form it can handle type lists up to 10 elements, but this can be extended by adding extra lines to the <code>Back()</code> macro</li> <li>the 'list' can contain a type only once</li> <li>the additional <code>ListId</code> type used in <code>NextInListHelper</code> declarations is there to allow types to be contained in multiple lists simultaneously </li> <li><code>Wrapper</code> is used to avoid actual instantiation of list element types and to support incomplete types as ListId </li> <li><code>PushBack()</code> 'calls' must be in the namespace of <code>ListId</code> (<code>NS1</code>) or <code>Wrapper</code> (the global scope) </li> <li>The processing of the list can be put in any namespace (<code>NS2</code>) </li> </ul>
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