| .. Data Types/Numeric//char_ |60 |
| |
| char\_ |
| ====== |
| |
| Synopsis |
| -------- |
| |
| .. parsed-literal:: |
| |
| template< |
| char N |
| > |
| struct char\_ |
| { |
| // |unspecified| |
| // ... |
| }; |
| |
| |
| Description |
| ----------- |
| |
| An |Integral Constant| wrapper for ``char``. |
| |
| |
| Header |
| ------ |
| |
| .. parsed-literal:: |
| |
| #include <boost/mpl/char.hpp> |
| |
| |
| Model of |
| -------- |
| |
| |Integral Constant| |
| |
| |
| Parameters |
| ---------- |
| |
| +---------------+-------------------------------+---------------------------+ |
| | Parameter | Requirement | Description | |
| +===============+===============================+===========================+ |
| | ``N`` | A character constant | A value to wrap. | |
| +---------------+-------------------------------+---------------------------+ |
| |
| Expression semantics |
| -------------------- |
| |
| |Semantics disclaimer...| |Integral Constant|. |
| |
| For arbitrary character constant ``c``: |
| |
| +-------------------+-----------------------------------------------------------+ |
| | Expression | Semantics | |
| +===================+===========================================================+ |
| | ``char_<c>`` | An |Integral Constant| ``x`` such that ``x::value == c`` | |
| | | and ``x::value_type`` is identical to ``char``. | |
| +-------------------+-----------------------------------------------------------+ |
| |
| |
| Example |
| ------- |
| |
| .. parsed-literal:: |
| |
| typedef char_<'c'> c; |
| |
| BOOST_MPL_ASSERT(( is_same< c::value_type, char > )); |
| BOOST_MPL_ASSERT(( is_same< c::type, c > )); |
| BOOST_MPL_ASSERT(( is_same< next< c >::type, char_<'d'> > )); |
| BOOST_MPL_ASSERT(( is_same< prior< c >::type, char_<'b'> > )); |
| BOOST_MPL_ASSERT_RELATION( (c::value), ==, 'c' ); |
| assert( c() == 'c' ); |
| |
| |
| See also |
| -------- |
| |
| |Data Types|, |Integral Constant|, |int_|, |size_t|, |integral_c| |
| |
| |
| .. copyright:: Copyright © 2009 Eric Niebler |
| Distributed under the Boost Software License, Version 1.0. (See accompanying |
| file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |