# 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 e028efd1e7.

### boost/vmd/assert_is_number.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_NUMBER_HPP)
#define BOOST_VMD_ASSERT_IS_NUMBER_HPP

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

/*

The succeeding comments in this file are in doxygen format.

*/

/** \file
*/

/** \def BOOST_VMD_ASSERT_IS_NUMBER(sequence)

\brief Asserts that the sequence is a number.

The macro checks that the parameter is a number.
If it is not a number, it forces a compiler error.

The macro normally checks for a number 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 possible number.

@code

returns  = Normally the macro returns nothing.

If the sequence is a number, nothing is
output.

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 a number 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 a
number.

@endcode

*/

#if !BOOST_VMD_ASSERT_DATA

#define BOOST_VMD_ASSERT_IS_NUMBER(sequence)

#else

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

#define BOOST_VMD_ASSERT_IS_NUMBER(sequence) \
BOOST_VMD_ASSERT \
( \
BOOST_VMD_IS_NUMBER(sequence), \
BOOST_VMD_IS_NUMBER_ASSERT_ERROR \
) \
/**/

#endif // !BOOST_VMD_ASSERT_DATA