# Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world.

This is the documentation for a snapshot of the develop branch, built from commit c73fda95e0.

### boost/vmd/get_type.hpp


//  (C) Copyright Edward Diener 2011-2015
//  Use, modification and distribution are subject to the Boost Software License,
//  Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at

#if !defined(BOOST_VMD_GET_TYPE_HPP)
#define BOOST_VMD_GET_TYPE_HPP

#include <boost/vmd/detail/setup.hpp>

#include <boost/vmd/detail/sequence_type.hpp>

/*

The succeeding comments in this file are in doxygen format.

*/

/** \file
*/

/** \def BOOST_VMD_GET_TYPE(...)

\brief Returns the type of a sequence as a VMD type.

The first variadic parameter is required and is the sequence whose type we are getting.

The optional variadic parameters are return type parameters.

The macro returns the type of a sequence as a VMD type. The type of an empty sequence
is always BOOST_VMD_TYPE_EMPTY and the type of a multi-element is always
BOOST_VMD_TYPE_SEQUENCE. The type of a single-element sequence is the
type of that single element.

The type returned can be modified by specifying an optional return type parameter.

If BOOST_VMD_RETURN_TYPE, the default, is specified the specific type of the element
is returned.

If BOOST_VMD_RETURN_TYPE_ARRAY is specified
an array type is returned if the element is an array, else a tuple
type is returned if the element is a tuple, else the actual type
is returned for non-tuple data.

If BOOST_VMD_RETURN_TYPE_LIST is specified
a list type is returned if the element is a list, else a tuple
type is returned if the element is a tuple, else the actual type
is returned for non-tuple data.

If BOOST_VMD_RETURN_TYPE_TUPLE is specified
a tuple type is returned for all tuple-like data, else the actual type
is returned for non-tuple data.

If BOOST_VMD_RETURN_NO_TYPE is specified it is ignored since the macro
always returns the type of the sequence.

If more than one return type optional parameter is specified the last
one specified determines the return type.

returns = the type of the sequence as a VMD type.

*/

#define BOOST_VMD_GET_TYPE(...) \
BOOST_VMD_DETAIL_SEQUENCE_TYPE(__VA_ARGS__) \
/**/

/** \def BOOST_VMD_GET_TYPE_D(d,...)

\brief Returns the type of a sequence as a VMD type. Re-entrant version.

d         = The next available BOOST_PP_WHILE iteration. <br/>

The first variadic parameter is required and is the sequence whose type we are getting.

The optional variadic parameters are return type parameters.

The macro returns the type of a sequence as a VMD type. The type of an empty sequence
is always BOOST_VMD_TYPE_EMPTY and the type of a multi-element is always
BOOST_VMD_TYPE_SEQUENCE. The type of a single-element sequence is the
type of that single element.

The type returned can be modified by specifying an optional return type parameter.

If BOOST_VMD_RETURN_TYPE, the default, is specified the specific type of the element
is returned.

If BOOST_VMD_RETURN_TYPE_ARRAY is specified
an array type is returned if the element is an array, else a tuple
type is returned if the element is a tuple, else the actual type
is returned for non-tuple data.

If BOOST_VMD_RETURN_TYPE_LIST is specified
a list type is returned if the element is a list, else a tuple
type is returned if the element is a tuple, else the actual type
is returned for non-tuple data.

If BOOST_VMD_RETURN_TYPE_TUPLE is specified
a tuple type is returned for all tuple-like data, else the actual type
is returned for non-tuple data.

If BOOST_VMD_RETURN_NO_TYPE is specified it is ignored since the macro
always returns the type of the sequence.

If more than one return type optional parameter is specified the last
one specified determines the return type.

returns = the type of the sequence as a VMD type.

*/

#define BOOST_VMD_GET_TYPE_D(d,...) \
BOOST_VMD_DETAIL_SEQUENCE_TYPE_D(d,__VA_ARGS__) \
/**/