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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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51
include/boost/preprocessor/cat.hpp
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@ -13,50 +13,13 @@
* See http://www.boost.org for most recent version.
*/
/** <P>Delays the catenation of X and Y.</P>
/** <p>Concatenates <code>X</code> and <code>Y</code> after they are macro
expanded.</p>
<P>For example,</P>
<PRE>
#define STATIC_ASSERT(EXPR)\
enum\
{ BOOST_PP_CAT(static_check_,__LINE__) = (EXPR) ? 1 : -1\
};\
typedef char\
BOOST_PP_CAT(static_assert_,__LINE__)\
[ BOOST_PP_CAT(static_check_,__LINE__)\
]
// ...
STATIC_ASSERT(sizeof(int) <= sizeof(long));
</PRE>
<P>expands to:</P>
<PRE>
enum
{ static_check_152 = (sizeof(int) <= sizeof(long)) ? 1 : -1
};
typedef char
static_assert_152
[ static_check_152
];
</PRE>
<P>Using BOOST_PP_CAT() above lets the PP expand the __LINE__. If the above
code would use the ## operator directly then __LINE__ would not be expanded and
the above would expand to:</P>
<PRE>
enum
{ static_check___LINE__ = (sizeof(int) <= sizeof(long)) ? 1 : -1
};
typedef char
static_assert___LINE__
[ static_check___LINE__
];
</PRE>
<h3>Example</h3>
<ul>
<li><a href="../../example/static_assert.c">static_assert.c</a></li>
</ul>
*/
#define BOOST_PP_CAT(X,Y) BOOST_PP_CAT_DELAY(X,Y)
@ -65,6 +28,6 @@ the above would expand to:</P>
#define BOOST_PP_DO_CAT(X,Y) X##Y
#endif
/** <P>Obsolete. Use BOOST_PP_CAT().</P> */
/** <p>Obsolete. Use BOOST_PP_CAT().</p> */
#define BOOST_PREPROCESSOR_CAT(X,Y) BOOST_PP_CAT(X,Y)
#endif