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BOOST_MPL_LIMIT_MAP_SIZE

Synopsis

#if !defined(BOOST_MPL_LIMIT_MAP_SIZE)
#   define BOOST_MPL_LIMIT_MAP_SIZE \
        implementation-defined integral constant \
/**/
#endif

Description

BOOST_MPL_LIMIT_MAP_SIZE is an overridable configuration macro regulating the maximum arity of the map's variadic form. In this implementation of the library, BOOST_MPL_LIMIT_MAP_SIZE has a default value of 20. To override the default limit, define BOOST_MPL_LIMIT_MAP_SIZE to the desired maximum arity rounded up to the nearest multiple of ten before including any library header. [Note: Overriding will take effect only if the library is configured not to use preprocessed headers. See BOOST_MPL_CFG_NO_PREPROCESSED_HEADERS for more information. — end note]

Example

#define BOOST_MPL_CFG_NO_PREPROCESSED_HEADERS
#define BOOST_MPL_LIMIT_MAP_SIZE 10
#include <boost/mpl/map.hpp>
#include <boost/mpl/pair.hpp>
#include <boost/mpl/int.hpp>

using namespace boost::mpl;

template< int i > struct ints : pair< int_<i>,int_<i> > {};

typedef map< ints<1> > m_1;
typedef map< ints<1>, ints<2>, ints<3>, ints<4>, ints<5>
    ints<6>, ints<7>, ints<8>, ints<9>, ints<10> > m_10;

// typedef map< ints<1>, ints<2>, ints<3>, ints<4>, ints<5>
//     ints<6>, ints<7>, ints<8>, ints<9>, ints<10>, ints<11> > m_11; // error!

See also

Configuration, BOOST_MPL_CFG_NO_PREPROCESSED_HEADERS, BOOST_MPL_LIMIT_SET_SIZE