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<div><h2 class="title">
<a name="variadic_macro_data"></a>Chapter&#160;1.&#160;The Variadic Macro Data Library 1.9</h2></div>
<div><div class="author"><h3 class="author">
<span class="firstname">Edward</span> <span class="surname">Diener</span>
</h3></div></div>
<div><p class="copyright">Copyright &#169; 2010-2017 Tropic Software
      East Inc</p></div>
</div></div>
<div class="toc">
<p><b>Table of Contents</b></p>
<dl class="toc">
<dt><span class="section"><a href="index.html#variadic_macro_data.vmd_intro">Introduction</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_naming.html">Naming conventions</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_whyhow.html">Why and how to use</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_vmacros.html">Using variadic macros</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_vc.html">Visual C++ define</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_detail.html">Functional groups</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_data_types.html">Data types</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_specific.html">Specific macros for working
    with data types</a></span></dt>
<dd><dl>
<dt><span class="section"><a href="variadic_macro_data/vmd_specific.html#variadic_macro_data.vmd_specific.vmd_test_empty">Emptiness</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_specific/vmd_constraints.html">Macro
      constraints</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_specific/vmd_identifier.html">Identifiers</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_specific/vmd_number.html">Numbers</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_specific/vmd_type.html">Types</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_specific/vmd_pp_data_types.html">VMD
      and Boost PP data types</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_specific/vmd_identifying.html">Identifying
      data types</a></span></dt>
</dl></dd>
<dt><span class="section"><a href="variadic_macro_data/vmd_generic.html">Generic macros for working
    with data types</a></span></dt>
<dd><dl>
<dt><span class="section"><a href="variadic_macro_data/vmd_generic.html#variadic_macro_data.vmd_generic.vmd_sequence">Parsing
      sequences</a></span></dt>
<dd><dl>
<dt><span class="section"><a href="variadic_macro_data/vmd_generic.html#variadic_macro_data.vmd_generic.vmd_sequence.vmd_sequence_convert">Converting
        sequences</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_generic.html#variadic_macro_data.vmd_generic.vmd_sequence.vmd_sequence_access">Accessing
        a sequence element</a></span></dt>
</dl></dd>
<dt><span class="section"><a href="variadic_macro_data/vmd_generic/vmd_convert_sequence.html">Getting
      the type of data</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_generic/vmd_assert.html">Testing for
      equality and inequality</a></span></dt>
</dl></dd>
<dt><span class="section"><a href="variadic_macro_data/vmd_modifiers.html">Macros with modifiers</a></span></dt>
<dd><dl>
<dt><span class="section"><a href="variadic_macro_data/vmd_modifiers.html#variadic_macro_data.vmd_modifiers.vmd_modifiers_return_type">Return
      type modifiers</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_modifiers/vmd_modifiers_filter.html">Filtering
      modifiers</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_modifiers/vmd_modifiers_identifier.html">Identifier
      modifiers</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_modifiers/vmd_modifiers_splitting.html">Splitting
      modifiers</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_modifiers/vmd_modifiers_index.html">Index
      modifiers</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_modifiers/vmd_modifiers_single.html">Modifiers
      and the single-element sequence</a></span></dt>
</dl></dd>
<dt><span class="section"><a href="variadic_macro_data/vmd_identifier_subtype.html">Identifier
    subtypes</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_useful.html">Useful variadic macros
    not in Boost PP</a></span></dt>
<dd><dl>
<dt><span class="section"><a href="variadic_macro_data/vmd_useful.html#variadic_macro_data.vmd_useful.vmd_assert">Asserting
      and data types</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_useful/vmd_identity.html">Generating
      emptiness and identity</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_useful/vmd_empty_ppdata.html">Functionality
      for "empty" seqs and tuples</a></span></dt>
</dl></dd>
<dt><span class="section"><a href="variadic_macro_data/vmd_internal_macros.html">Controlling internal
    usage</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_reentrant.html">Boost PP re-entrant
    versions</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_dynamic_typing.html">Input as dynamic
    types</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_vc_isms.html">Visual C++ gotchas in
    VMD</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_conv.html">Version 1.7 to 1.8 conversion</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_examples.html">Examples using VMD functionality</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data_reference.html">Variadic Macro Data Reference</a></span></dt>
<dd><dl>
<dt><span class="section"><a href="variadic_macro_data_reference.html#header.boost.vmd.array.to_seq_hpp">Header &lt;boost/vmd/array/to_seq.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/list/to_seq_hpp.html">Header &lt;boost/vmd/list/to_seq.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/to_seq_hpp.html">Header &lt;boost/vmd/to_seq.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/tuple/to_seq_hpp.html">Header &lt;boost/vmd/tuple/to_seq.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/array/to_tuple_hpp.html">Header &lt;boost/vmd/array/to_tuple.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/list/to_tuple_hpp.html">Header &lt;boost/vmd/list/to_tuple.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/seq/to_tuple_hpp.html">Header &lt;boost/vmd/seq/to_tuple.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/to_tuple_hpp.html">Header &lt;boost/vmd/to_tuple.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/assert_hpp.html">Header &lt;boost/vmd/assert.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/assert_is_array_hpp.html">Header &lt;boost/vmd/assert_is_array.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/assert_is_empty_hpp.html">Header &lt;boost/vmd/assert_is_empty.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/assert_is_identifier_hpp.html">Header &lt;boost/vmd/assert_is_identifier.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/assert_is_list_hpp.html">Header &lt;boost/vmd/assert_is_list.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/assert_is_number_hpp.html">Header &lt;boost/vmd/assert_is_number.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/assert_is_seq_hpp.html">Header &lt;boost/vmd/assert_is_seq.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/assert_is_tuple_hpp.html">Header &lt;boost/vmd/assert_is_tuple.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/assert_is_type_hpp.html">Header &lt;boost/vmd/assert_is_type.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/elem_hpp.html">Header &lt;boost/vmd/elem.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/empty_hpp.html">Header &lt;boost/vmd/empty.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/enum_hpp.html">Header &lt;boost/vmd/enum.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/equal_hpp.html">Header &lt;boost/vmd/equal.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/get_type_hpp.html">Header &lt;boost/vmd/get_type.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/identity_hpp.html">Header &lt;boost/vmd/identity.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/is_array_hpp.html">Header &lt;boost/vmd/is_array.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/is_empty_hpp.html">Header &lt;boost/vmd/is_empty.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/is_empty_array_hpp.html">Header &lt;boost/vmd/is_empty_array.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/is_empty_list_hpp.html">Header &lt;boost/vmd/is_empty_list.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/is_identifier_hpp.html">Header &lt;boost/vmd/is_identifier.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/is_list_hpp.html">Header &lt;boost/vmd/is_list.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/is_multi_hpp.html">Header &lt;boost/vmd/is_multi.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/is_number_hpp.html">Header &lt;boost/vmd/is_number.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/is_parens_empty_hpp.html">Header &lt;boost/vmd/is_parens_empty.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/is_seq_hpp.html">Header &lt;boost/vmd/is_seq.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/is_tuple_hpp.html">Header &lt;boost/vmd/is_tuple.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/is_type_hpp.html">Header &lt;boost/vmd/is_type.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/is_unary_hpp.html">Header &lt;boost/vmd/is_unary.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/not_equal_hpp.html">Header &lt;boost/vmd/not_equal.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/seq/is_vmd_seq_hpp.html">Header &lt;boost/vmd/seq/is_vmd_seq.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/seq/pop_back_hpp.html">Header &lt;boost/vmd/seq/pop_back.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/tuple/pop_back_hpp.html">Header &lt;boost/vmd/tuple/pop_back.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/seq/pop_front_hpp.html">Header &lt;boost/vmd/seq/pop_front.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/tuple/pop_front_hpp.html">Header &lt;boost/vmd/tuple/pop_front.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/seq/push_back_hpp.html">Header &lt;boost/vmd/seq/push_back.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/tuple/push_back_hpp.html">Header &lt;boost/vmd/tuple/push_back.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/seq/push_front_hpp.html">Header &lt;boost/vmd/seq/push_front.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/tuple/push_front_hpp.html">Header &lt;boost/vmd/tuple/push_front.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/seq/remove_hpp.html">Header &lt;boost/vmd/seq/remove.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/tuple/remove_hpp.html">Header &lt;boost/vmd/tuple/remove.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/seq/size_hpp.html">Header &lt;boost/vmd/seq/size.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/size_hpp.html">Header &lt;boost/vmd/size.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/tuple/size_hpp.html">Header &lt;boost/vmd/tuple/size.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/seq/to_array_hpp.html">Header &lt;boost/vmd/seq/to_array.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/to_array_hpp.html">Header &lt;boost/vmd/to_array.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/tuple/to_array_hpp.html">Header &lt;boost/vmd/tuple/to_array.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/seq/to_list_hpp.html">Header &lt;boost/vmd/seq/to_list.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/to_list_hpp.html">Header &lt;boost/vmd/to_list.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/tuple/to_list_hpp.html">Header &lt;boost/vmd/tuple/to_list.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
<dt><span class="section"><a href="header/boost/vmd/tuple/is_vmd_tuple_hpp.html">Header &lt;boost/vmd/tuple/is_vmd_tuple.hpp&gt;</a></span></dt>
<dd><dl></dl></dd>
</dl></dd>
<dt><span class="section"><a href="variadic_macro_data/vmd_design.html">Design</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_compilers.html">Compilers</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_history.html">History</a></span></dt>
<dt><span class="section"><a href="variadic_macro_data/vmd_ack.html">Acknowledgements</a></span></dt>
<dt><span class="section"><a href="index/s24.html">Index</a></span></dt>
</dl>
</div>
<div class="section">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="variadic_macro_data.vmd_intro"></a><a class="link" href="index.html#variadic_macro_data.vmd_intro" title="Introduction">Introduction</a>
</h2></div></div></div>
<p>
      Welcome to the Variadic Macro Data library.
    </p>
<p>
      The Variadic Macro Data library, referred to hereafter as VMD for short, is
      a library of variadic macros which provide enhancements to the functionality
      in the Boost preprocessor library ( Boost PP ), especially as it relates to
      preprocessor data types.
    </p>
<p>
      The preprocessor data types with which VMD has specific functionality are emptiness,
      identifiers, numbers ( a subset of identifiers ), types ( a subset of identifiers
      ), Boost PP arrays, Boost PP lists, Boost PP seqs, Boost PP tuples, and sequences.
      The first four are basic preprocessor data types while the latter five are
      composite preprocessor data types. A sequence is zero or more of the other
      preprocessor data types following each other.
    </p>
<h4>
<a name="variadic_macro_data.vmd_intro.h0"></a>
      <span class="phrase"><a name="variadic_macro_data.vmd_intro.data_type_examples"></a></span><a class="link" href="index.html#variadic_macro_data.vmd_intro.data_type_examples">Data
      type examples</a>
    </h4>
<div class="table">
<a name="variadic_macro_data.vmd_intro.dwe"></a><p class="title"><b>Table&#160;1.1.&#160;Data types with examples</b></p>
<div class="table-contents"><table class="table" summary="Data types with examples">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
              <p>
                Type
              </p>
            </th>
<th>
              <p>
                Example
              </p>
            </th>
</tr></thead>
<tbody>
<tr>
<td>
              <p>
                identifier
              </p>
            </td>
<td>
              <p>
                anyname
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                number
              </p>
            </td>
<td>
              <p>
                47
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                type
              </p>
            </td>
<td>
              <p>
                BOOST_VMD_TYPE_NUMBER
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                array
              </p>
            </td>
<td>
              <p>
                (4,(an_identifier,156,BOOST_VMD_TYPE_IDENTIFIER))
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                list
              </p>
            </td>
<td>
              <p>
                (78,(some_identifier,(BOOST_VMD_TYPE_TYPE,BOOST_PP_NIL)))
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                seq
              </p>
            </td>
<td>
              <p>
                (identifier)(89)(245)
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                tuple
              </p>
            </td>
<td>
              <p>
                (any_id,175,BOOST_VMD_TYPE_LIST,happy,21)
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                sequence
              </p>
            </td>
<td>
              <p>
                tree 59 (56,BOOST_VMD_TYPE_SEQ) (128)(fire)(clown) (47,(BOOST_VMD_TYPE_TUPLE,BOOST_PP_NIL))
              </p>
            </td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break"><p>
      Emptiness is the lack of any preprocessing tokens. A macro which expands to
      nothing, as in:
    </p>
<pre class="programlisting"><span class="preprocessor">#define</span> <span class="identifier">RETURN_NOTHING</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span>
</pre>
<p>
      is said to return emptiness. Conversely a macro could accept nothing when invoked,
      such as in:
    </p>
<pre class="programlisting"><span class="identifier">RETURN_NOTHING</span><span class="special">()</span>
</pre>
<p>
      Finally emptiness can be part of any composite data type as in:
    </p>
<pre class="programlisting"><span class="special">(</span><span class="number">45</span><span class="special">,,</span><span class="identifier">some_name</span><span class="special">)</span>
</pre>
<p>
      where the second tuple element is empty.
    </p>
<h4>
<a name="variadic_macro_data.vmd_intro.h1"></a>
      <span class="phrase"><a name="variadic_macro_data.vmd_intro.what_is_the_advantage"></a></span><a class="link" href="index.html#variadic_macro_data.vmd_intro.what_is_the_advantage">What
      is the advantage ?</a>
    </h4>
<p>
      VMD can identify any of the preprocessor data types previously mentioned, and
      can parse sequences into their individual preprocessor data types. You may
      well ask why that is important.
    </p>
<p>
      In Boost PP macro programming a great deal of the control logic of designing
      a macro is based on the support Boost PP has for numbers and testing for the
      value of a number, in particular 0 and 1 to represent boolean choices. Essentially
      Boost PP often uses the value of a number to control the logic in a macro's
      design.
    </p>
<p>
      VMD does not attempt, in any way, to duplicate Boost PP's support for testing
      the value of numbers or of the boolean 0 or 1 values, but just reuses that
      functionality. What VMD offers, which goes beyond Boost PP, is a system for
      deciphering the preprocessor data types, as well as comparing any of the preprocessor
      data types for equality to any given value. This allows macro logic to be designed
      in a more flexible way, relying on the type of data and/or the value of the
      data. If this intrigues you, continue reading to understand how you can use
      VMD to do macro programming.
    </p>
<h4>
<a name="variadic_macro_data.vmd_intro.h2"></a>
      <span class="phrase"><a name="variadic_macro_data.vmd_intro.functionality_areas"></a></span><a class="link" href="index.html#variadic_macro_data.vmd_intro.functionality_areas">Functionality
      areas</a>
    </h4>
<p>
      The functionality of the library may be summed up as:
    </p>
<div class="orderedlist"><ol class="orderedlist" type="1">
<li class="listitem">
          Provide a better way of testing for and using empty parameters and empty
          preprocessor data.
        </li>
<li class="listitem">
          Provide ways for testing/parsing for identifiers, numbers, types, tuples,
          arrays, lists, and seqs.
        </li>
<li class="listitem">
          Provide ways for testing/parsing sequences of identifiers, numbers, types,
          tuples, arrays, lists. and seqs.
        </li>
<li class="listitem">
          Provide some useful variadic macros not in Boost PP.
        </li>
</ol></div>
<p>
      The library is a header only library and all macros in the library are included
      by a single header, whose name is 'vmd.hpp'. Individual headers may be used
      for different functionality in the library and will be denoted when that functionality
      is explained.
    </p>
<p>
      All the macros in the library begin with the sequence 'BOOST_VMD_' to distinguish
      them from other macros the end-user might use. Therefore the end-user should
      not use any C++ identifiers, whether in macros or otherwise, which being with
      the sequence 'BOOST_VMD_'.
    </p>
<p>
      Use of the library is only dependent on Boost PP. The library also uses Boost
      detail lightweight_test.hpp for its own tests.
    </p>
</div>
</div>
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<td align="left"><p><small>Last revised: December 10, 2019 at 00:21:47 GMT</small></p></td>
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