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<title>Chapter 1. The Variadic Macro Data Library 1.9</title>
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<div class="chapter">
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<div class="titlepage"><div>
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<div><h2 class="title">
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<a name="variadic_macro_data"></a>Chapter 1. The Variadic Macro Data Library 1.9</h2></div>
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<div><div class="author"><h3 class="author">
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<span class="firstname">Edward</span> <span class="surname">Diener</span>
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</h3></div></div>
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<div><p class="copyright">Copyright © 2010-2017 Tropic Software
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East Inc</p></div>
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</div></div>
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<div class="toc">
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<p><b>Table of Contents</b></p>
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<dl class="toc">
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<dt><span class="section"><a href="index.html#variadic_macro_data.vmd_intro">Introduction</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_naming.html">Naming conventions</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_whyhow.html">Why and how to use</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_vmacros.html">Using variadic macros</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_vc.html">Visual C++ define</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_detail.html">Functional groups</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_data_types.html">Data types</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_specific.html">Specific macros for working
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with data types</a></span></dt>
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<dd><dl>
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<dt><span class="section"><a href="variadic_macro_data/vmd_specific.html#variadic_macro_data.vmd_specific.vmd_test_empty">Emptiness</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_specific/vmd_constraints.html">Macro
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constraints</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_specific/vmd_identifier.html">Identifiers</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_specific/vmd_number.html">Numbers</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_specific/vmd_type.html">Types</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_specific/vmd_pp_data_types.html">VMD
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and Boost PP data types</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_specific/vmd_identifying.html">Identifying
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data types</a></span></dt>
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</dl></dd>
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<dt><span class="section"><a href="variadic_macro_data/vmd_generic.html">Generic macros for working
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with data types</a></span></dt>
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<dd><dl>
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<dt><span class="section"><a href="variadic_macro_data/vmd_generic.html#variadic_macro_data.vmd_generic.vmd_sequence">Parsing
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sequences</a></span></dt>
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<dd><dl>
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<dt><span class="section"><a href="variadic_macro_data/vmd_generic.html#variadic_macro_data.vmd_generic.vmd_sequence.vmd_sequence_convert">Converting
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sequences</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_generic.html#variadic_macro_data.vmd_generic.vmd_sequence.vmd_sequence_access">Accessing
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a sequence element</a></span></dt>
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</dl></dd>
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<dt><span class="section"><a href="variadic_macro_data/vmd_generic/vmd_convert_sequence.html">Getting
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the type of data</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_generic/vmd_assert.html">Testing for
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equality and inequality</a></span></dt>
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</dl></dd>
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<dt><span class="section"><a href="variadic_macro_data/vmd_modifiers.html">Macros with modifiers</a></span></dt>
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<dd><dl>
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<dt><span class="section"><a href="variadic_macro_data/vmd_modifiers.html#variadic_macro_data.vmd_modifiers.vmd_modifiers_return_type">Return
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type modifiers</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_modifiers/vmd_modifiers_filter.html">Filtering
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modifiers</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_modifiers/vmd_modifiers_identifier.html">Identifier
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modifiers</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_modifiers/vmd_modifiers_splitting.html">Splitting
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modifiers</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_modifiers/vmd_modifiers_index.html">Index
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modifiers</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_modifiers/vmd_modifiers_single.html">Modifiers
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and the single-element sequence</a></span></dt>
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</dl></dd>
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<dt><span class="section"><a href="variadic_macro_data/vmd_identifier_subtype.html">Identifier
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subtypes</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_useful.html">Useful variadic macros
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not in Boost PP</a></span></dt>
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<dd><dl>
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<dt><span class="section"><a href="variadic_macro_data/vmd_useful.html#variadic_macro_data.vmd_useful.vmd_assert">Asserting
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and data types</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_useful/vmd_identity.html">Generating
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emptiness and identity</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_useful/vmd_empty_ppdata.html">Functionality
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for "empty" seqs and tuples</a></span></dt>
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</dl></dd>
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<dt><span class="section"><a href="variadic_macro_data/vmd_internal_macros.html">Controlling internal
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usage</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_reentrant.html">Boost PP re-entrant
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versions</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_dynamic_typing.html">Input as dynamic
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types</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_vc_isms.html">Visual C++ gotchas in
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VMD</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_conv.html">Version 1.7 to 1.8 conversion</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_examples.html">Examples using VMD functionality</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data_reference.html">Variadic Macro Data Reference</a></span></dt>
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<dd><dl>
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<dt><span class="section"><a href="variadic_macro_data_reference.html#header.boost.vmd.array.to_seq_hpp">Header <boost/vmd/array/to_seq.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/list/to_seq_hpp.html">Header <boost/vmd/list/to_seq.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/to_seq_hpp.html">Header <boost/vmd/to_seq.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/tuple/to_seq_hpp.html">Header <boost/vmd/tuple/to_seq.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/array/to_tuple_hpp.html">Header <boost/vmd/array/to_tuple.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/list/to_tuple_hpp.html">Header <boost/vmd/list/to_tuple.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/seq/to_tuple_hpp.html">Header <boost/vmd/seq/to_tuple.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/to_tuple_hpp.html">Header <boost/vmd/to_tuple.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/assert_hpp.html">Header <boost/vmd/assert.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/assert_is_array_hpp.html">Header <boost/vmd/assert_is_array.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/assert_is_empty_hpp.html">Header <boost/vmd/assert_is_empty.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/assert_is_identifier_hpp.html">Header <boost/vmd/assert_is_identifier.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/assert_is_list_hpp.html">Header <boost/vmd/assert_is_list.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/assert_is_number_hpp.html">Header <boost/vmd/assert_is_number.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/assert_is_seq_hpp.html">Header <boost/vmd/assert_is_seq.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/assert_is_tuple_hpp.html">Header <boost/vmd/assert_is_tuple.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/assert_is_type_hpp.html">Header <boost/vmd/assert_is_type.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/elem_hpp.html">Header <boost/vmd/elem.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/empty_hpp.html">Header <boost/vmd/empty.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/enum_hpp.html">Header <boost/vmd/enum.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/equal_hpp.html">Header <boost/vmd/equal.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/get_type_hpp.html">Header <boost/vmd/get_type.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/identity_hpp.html">Header <boost/vmd/identity.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/is_array_hpp.html">Header <boost/vmd/is_array.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/is_empty_hpp.html">Header <boost/vmd/is_empty.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/is_empty_array_hpp.html">Header <boost/vmd/is_empty_array.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/is_empty_list_hpp.html">Header <boost/vmd/is_empty_list.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/is_identifier_hpp.html">Header <boost/vmd/is_identifier.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/is_list_hpp.html">Header <boost/vmd/is_list.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/is_multi_hpp.html">Header <boost/vmd/is_multi.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/is_number_hpp.html">Header <boost/vmd/is_number.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/is_parens_empty_hpp.html">Header <boost/vmd/is_parens_empty.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/is_seq_hpp.html">Header <boost/vmd/is_seq.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/is_tuple_hpp.html">Header <boost/vmd/is_tuple.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/is_type_hpp.html">Header <boost/vmd/is_type.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/is_unary_hpp.html">Header <boost/vmd/is_unary.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/not_equal_hpp.html">Header <boost/vmd/not_equal.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/seq/is_vmd_seq_hpp.html">Header <boost/vmd/seq/is_vmd_seq.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/seq/pop_back_hpp.html">Header <boost/vmd/seq/pop_back.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/tuple/pop_back_hpp.html">Header <boost/vmd/tuple/pop_back.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/seq/pop_front_hpp.html">Header <boost/vmd/seq/pop_front.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/tuple/pop_front_hpp.html">Header <boost/vmd/tuple/pop_front.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/seq/push_back_hpp.html">Header <boost/vmd/seq/push_back.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/tuple/push_back_hpp.html">Header <boost/vmd/tuple/push_back.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/seq/push_front_hpp.html">Header <boost/vmd/seq/push_front.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/tuple/push_front_hpp.html">Header <boost/vmd/tuple/push_front.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/seq/remove_hpp.html">Header <boost/vmd/seq/remove.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/tuple/remove_hpp.html">Header <boost/vmd/tuple/remove.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/seq/size_hpp.html">Header <boost/vmd/seq/size.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/size_hpp.html">Header <boost/vmd/size.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/tuple/size_hpp.html">Header <boost/vmd/tuple/size.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/seq/to_array_hpp.html">Header <boost/vmd/seq/to_array.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/to_array_hpp.html">Header <boost/vmd/to_array.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/tuple/to_array_hpp.html">Header <boost/vmd/tuple/to_array.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/seq/to_list_hpp.html">Header <boost/vmd/seq/to_list.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/to_list_hpp.html">Header <boost/vmd/to_list.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/tuple/to_list_hpp.html">Header <boost/vmd/tuple/to_list.hpp></a></span></dt>
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<dd><dl></dl></dd>
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<dt><span class="section"><a href="header/boost/vmd/tuple/is_vmd_tuple_hpp.html">Header <boost/vmd/tuple/is_vmd_tuple.hpp></a></span></dt>
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<dd><dl></dl></dd>
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</dl></dd>
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<dt><span class="section"><a href="variadic_macro_data/vmd_design.html">Design</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_compilers.html">Compilers</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_history.html">History</a></span></dt>
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<dt><span class="section"><a href="variadic_macro_data/vmd_ack.html">Acknowledgements</a></span></dt>
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<dt><span class="section"><a href="index/s24.html">Index</a></span></dt>
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</dl>
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</div>
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<div class="section">
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<div class="titlepage"><div><div><h2 class="title" style="clear: both">
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<a name="variadic_macro_data.vmd_intro"></a><a class="link" href="index.html#variadic_macro_data.vmd_intro" title="Introduction">Introduction</a>
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</h2></div></div></div>
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<p>
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Welcome to the Variadic Macro Data library.
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</p>
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<p>
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The Variadic Macro Data library, referred to hereafter as VMD for short, is
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a library of variadic macros which provide enhancements to the functionality
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in the Boost preprocessor library ( Boost PP ), especially as it relates to
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preprocessor data types.
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</p>
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<p>
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The preprocessor data types with which VMD has specific functionality are emptiness,
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identifiers, numbers ( a subset of identifiers ), types ( a subset of identifiers
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), Boost PP arrays, Boost PP lists, Boost PP seqs, Boost PP tuples, and sequences.
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The first four are basic preprocessor data types while the latter five are
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composite preprocessor data types. A sequence is zero or more of the other
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preprocessor data types following each other.
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</p>
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<h4>
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<a name="variadic_macro_data.vmd_intro.h0"></a>
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|
<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 1.1. 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>
|
|
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
|
|
<td align="left"><p><small>Last revised: August 14, 2019 at 12:05:24 GMT</small></p></td>
|
|
<td align="right"><div class="copyright-footer"></div></td>
|
|
</tr></table>
|
|
<hr>
|
|
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