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Updated docs

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[SVN r12687]
This commit is contained in:
Vesa Karvonen
2002-02-04 13:32:28 +00:00
parent 6fa0d837a3
commit 8432192ac0
66 changed files with 627 additions and 712 deletions
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57
include/boost/preprocessor/empty.hpp
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@ -13,60 +13,15 @@
* See http://www.boost.org for most recent version.
*/
/** <P>Expands to nothing. Used with BOOST_PP_IF() and as an unused parameter.</P>
/** <p>Expands to nothing. Used with BOOST_PP_IF() and as an unused parameter.</p>
<P>Example usage as the implementation of BOOST_PP_COMMA_IF(C):</P>
<PRE>
#define BOOST_PP_COMMA_IF(C)\
BOOST_PP_IF(C,BOOST_PP_COMMA,BOOST_PP_EMPTY)()
</PRE>
<P>Example usage as an unused macro parameter:</P>
<PRE>
#define BOOST_PP_DEF(CV)\
template<class base>\
CV() typename implement_subscript_using_begin_subscript<base>::value_type&\
implement_subscript_using_begin_subscript<base>::operator[]\
( index_type\
i\
) CV()\
{ return base::begin()[i];\
}
BOOST_PP_DEF(BOOST_PP_EMPTY)
BOOST_PP_DEF(const BOOST_PP_EMPTY)
#undef BOOST_PP_DEF
</PRE>
<P>The above expands to:</P>
<PRE>
template<class base>
typename implement_subscript_using_begin_subscript<base>::value_type&
implement_subscript_using_begin_subscript<base>::operator[]
( index_type
i
)
{ return base::begin()[i];
}
template<class base>
const typename implement_subscript_using_begin_subscript<base>::value_type&
implement_subscript_using_begin_subscript<base>::operator[]
( index_type
i
) const
{ return base::begin()[i];
}
</PRE>
<P>In case you wonder, the above code is part of a generalized layer for
implementing the subscripting operators of a random access container.</P>
<h3>Example</h3>
<ul>
<li><a href="../../example/subscript_layer.cpp">subscript_layer.cpp</a></li>
</ul>
*/
#define BOOST_PP_EMPTY()
/** <P>Obsolete. Use BOOST_PP_EMPTY().</P> */
/** <p>Obsolete. Use BOOST_PP_EMPTY().</p> */
#define BOOST_PREPROCESSOR_EMPTY()
#endif