# Boost C++ Libraries

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### boost/vmd/assert_is_identifier.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_ASSERT_IS_IDENTIFIER_HPP)
#define BOOST_VMD_ASSERT_IS_IDENTIFIER_HPP

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

/*

The succeeding comments in this file are in doxygen format.

*/

/** \file
*/

/** \def BOOST_VMD_ASSERT_IS_IDENTIFIER(...)

\brief Asserts that the sequence is an identifier.

The macro checks that the sequence is an identifier.
If it is not an identifier, it forces a compiler error.

The macro normally checks for an identifier only in
debug mode. However an end-user can force the macro
to check or not check by defining the macro
BOOST_VMD_ASSERT_DATA to 1 or 0 respectively.

sequence         = A sequence to test as an identifier. <br/>
ids (optional)   = The data may take one of two forms:
it is either one or more single identifiers
or a single Boost PP tuple of identifiers.

@code

returns = Normally the macro returns nothing.

If the sequence is an identifier, nothing is
output. If optional ids are specified, for the
sequence to be an identifier it must be an
identifier that matches one of the optional
ids.

For VC++, because there is no sure way of forcing
a compiler error from within a macro without producing
output, if the sequence is not an identifier the
macro forces a compiler error by outputting invalid C++.

For all other compilers a compiler error is forced
without producing output if the sequence is not an
identifier.

@endcode

Identifiers are registered in VMD with:

@code

#define BOOST_VMD_REG_XXX (XXX) where XXX is a v-identifier.

@endcode

The identifier must be registered to be found.

Identifiers are pre-detected in VMD with:

@code

#define BOOST_VMD_DETECT_XXX_XXX where XXX is an identifier.

@endcode

If you specify optional ids and have not specified the detection
of an optional id, that id will never match an identifier.

*/

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

\brief Asserts that the sequence is an identifier. Re-entrant version.

The macro checks that the sequence is an identifier.
If it is not an identifier, it forces a compiler error.

The macro normally checks for an identifier only in
debug mode. However an end-user can force the macro
to check or not check by defining the macro
BOOST_VMD_ASSERT_DATA to 1 or 0 respectively.

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

sequence         = A sequence to test as an identifier. <br/>
ids (optional)   = The data may take one of two forms:
it is either one or more single identifiers
or a single Boost PP tuple of identifiers.

@code

returns = Normally the macro returns nothing.

If the sequence is an identifier, nothing is
output. If optional ids are specified, for the
sequence to be an identifier it must be an
identifier that matches one of the optional
ids.

For VC++, because there is no sure way of forcing
a compiler error from within a macro without producing
output, if the sequence is not an identifier the
macro forces a compiler error by outputting invalid C++.

For all other compilers a compiler error is forced
without producing output if the sequence is not an
identifier.

@endcode

Identifiers are registered in VMD with:

@code

#define BOOST_VMD_REG_XXX (XXX) where XXX is a v-identifier.

@endcode

The identifier must be registered to be found.

Identifiers are pre-detected in VMD with:

@code

#define BOOST_VMD_DETECT_XXX_XXX where XXX is an identifier.

@endcode

If you specify optional ids and have not specified the detection
of an optional id, that id will never match an identifier.

*/

#if !BOOST_VMD_ASSERT_DATA

#define BOOST_VMD_ASSERT_IS_IDENTIFIER(...)
#define BOOST_VMD_ASSERT_IS_IDENTIFIER_D(d,...)

#else

#include <boost/vmd/assert.hpp>
#include <boost/vmd/is_identifier.hpp>

#define BOOST_VMD_ASSERT_IS_IDENTIFIER(...) \
BOOST_VMD_ASSERT \
( \
BOOST_VMD_IS_IDENTIFIER(__VA_ARGS__), \
BOOST_VMD_IDENTIFIER_ASSERT_ERROR \
) \
/**/

#define BOOST_VMD_ASSERT_IS_IDENTIFIER_D(d,...) \
BOOST_VMD_ASSERT \
( \
BOOST_VMD_IS_IDENTIFIER_D(d,__VA_ARGS__), \
BOOST_VMD_IDENTIFIER_ASSERT_ERROR \
) \
/**/

#endif // !BOOST_VMD_ASSERT_DATA