boost_preprocessor/doc/data/sequences.html

<html>
	<head>
		<title>sequences.html</title>
		<link rel="stylesheet" type="text/css" href="../styles.css">
	</head>
	<body>
		<h4>
			Sequences
		</h4>
		<div>
			A <i>sequence</i> (abbreviated to <i>seq</i>) is a group of adjacent parenthesized elements. For example,
		</div>
		<div class="code">
			(<i>a</i>)(<i>b</i>)(<i>c</i>)
		</div>
		<div>
			...is a <i>seq</i> of <i>3</i> elements--<i>a</i>, <i>b</i>, and <i>c</i>.
		</div>
		<div>
			<i>Sequences</i> are data structures that merge the properties of both <i>lists</i> and
			<i>tuples</i> with the exception that a <i>seq</i> cannot be empty.&nbsp; 
			Therefore, an "empty" <i>seq</i> is considered a special case scenario that 
			must be handled separately in C++.
		</div>
		<div class="code">
			<pre>
#define SEQ (x)(y)(z)
#define REVERSE(s, state, elem) (elem) state
   // append to head                  ^

BOOST_PP_SEQ_FOLD_LEFT(REVERSE, BOOST_PP_EMPTY, SEQ)()
   //                           #1                  #2
   // 1) placeholder for "empty" seq
   // 2) remove placeholder

#define SEQ_B (1)(2)(3)
#define INC(s, state, elem) state (BOOST_PP_INC(elem))
   // append to tail             ^

BOOST_PP_SEQ_FOLD_RIGHT(INC, BOOST_PP_SEQ_NIL, SEQ)
   //                        ^
   // special placeholder that will be "eaten"
   // by appending to the tail
</pre>
		</div>
		<div>
			<i>Sequences</i> are extremely efficient.&nbsp; Element access speed approaches 
			random access--even with <i>seqs</i> of up to <i>256</i> elements.&nbsp; This 
			is because element access (among other things) is implemented iteratively 
			rather than recursively.&nbsp; Therefore, elements can be accessed at extremely 
			high indices even on preprocessors with low maximum expansion depths.
		</div>
		<div>
			Elements of a <i>seq</i> can be extracted with <b>BOOST_PP_SEQ_ELEM</b>.
		</div>
		<h4>
			Primitives
		</h4>
		<ul>
			<li>
				<a href="../ref/seq_elem.html">BOOST_PP_SEQ_ELEM</a></li>
		</ul>
	<hr size="1">
	<div style="margin-left: 0px;">
		<i><EFBFBD> Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
		</br><i><EFBFBD> Copyright Paul Mensonides 2002</i>
	</div>
	<div style="margin-left: 0px;">
		<p><small>Distributed under the Boost Software License, Version 1.0. (See
		accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
		copy at <a href=
		"http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
	</div>
	</body>
</html>
-												preliminary set support


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+								<html>
-												set -> seq


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+									<head>
-												set -> seq


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+										<title>sequences.html</title>
-												set -> seq


[SVN r16150]

											
										
										
											2002-11-07 23:39:29 +00:00
+										<link rel="stylesheet" type="text/css" href="../styles.css">
 									</head>
 									<body>
 										<h4>
-												set -> seq


[SVN r16152]

											
										
										
											2002-11-08 02:12:35 +00:00
+											Sequences
-												set -> seq


[SVN r16150]

											
										
										
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+										</h4>
 										<div>
-												set -> seq


[SVN r16152]

											
										
										
											2002-11-08 02:12:35 +00:00
+											A <i>sequence</i> (abbreviated to <i>seq</i>) is a group of adjacent parenthesized elements. For example,
-												set -> seq


[SVN r16150]

											
										
										
											2002-11-07 23:39:29 +00:00
+										</div>
 										<div class="code">
 											(<i>a</i>)(<i>b</i>)(<i>c</i>)
 										</div>
 										<div>
 											...is a <i>seq</i> of <i>3</i> elements--<i>a</i>, <i>b</i>, and <i>c</i>.
 										</div>
 										<div>
-												set -> seq


[SVN r16152]

											
										
										
											2002-11-08 02:12:35 +00:00
+											<i>Sequences</i> are data structures that merge the properties of both <i>lists</i> and
 											<i>tuples</i> with the exception that a <i>seq</i> cannot be empty.&nbsp;
-												set -> seq


[SVN r16150]

											
										
										
											2002-11-07 23:39:29 +00:00
+											Therefore, an "empty" <i>seq</i> is considered a special case scenario that
 											must be handled separately in C++.
 										</div>
 										<div class="code">
 											<pre>
 								#define SEQ (x)(y)(z)
-												preliminary set support


[SVN r15908]

											
										
										
											2002-10-13 05:47:23 +00:00
+								#define REVERSE(s, state, elem) (elem) state
 								   // append to head                  ^
-												set -> seq


[SVN r16150]

											
										
										
											2002-11-07 23:39:29 +00:00
+								BOOST_PP_SEQ_FOLD_LEFT(REVERSE, BOOST_PP_EMPTY, SEQ)()
-												preliminary set support


[SVN r15908]

											
										
										
											2002-10-13 05:47:23 +00:00
+								   //                           #1                  #2
-												set -> seq


[SVN r16150]

											
										
										
											2002-11-07 23:39:29 +00:00
+								   // 1) placeholder for "empty" seq
-												preliminary set support


[SVN r15908]

											
										
										
											2002-10-13 05:47:23 +00:00
+								   // 2) remove placeholder
-												set -> seq


[SVN r16150]

											
										
										
											2002-11-07 23:39:29 +00:00
+								#define SEQ_B (1)(2)(3)
-												preliminary set support


[SVN r15908]

											
										
										
											2002-10-13 05:47:23 +00:00
+								#define INC(s, state, elem) state (BOOST_PP_INC(elem))
 								   // append to tail             ^
-												set -> seq


[SVN r16150]

											
										
										
											2002-11-07 23:39:29 +00:00
+								BOOST_PP_SEQ_FOLD_RIGHT(INC, BOOST_PP_SEQ_NIL, SEQ)
-												preliminary set support


[SVN r15908]

											
										
										
											2002-10-13 05:47:23 +00:00
+								   //                        ^
 								   // special placeholder that will be "eaten"
 								   // by appending to the tail
-												set -> seq


[SVN r16150]

											
										
										
											2002-11-07 23:39:29 +00:00
+								</pre>
 										</div>
 										<div>
-												set -> seq


[SVN r16152]

											
										
										
											2002-11-08 02:12:35 +00:00
+											<i>Sequences</i> are extremely efficient.&nbsp; Element access speed approaches
-												set -> seq


[SVN r16150]

											
										
										
											2002-11-07 23:39:29 +00:00
+											random access--even with <i>seqs</i> of up to <i>256</i> elements.&nbsp; This
 											is because element access (among other things) is implemented iteratively
 											rather than recursively.&nbsp; Therefore, elements can be accessed at extremely
 											high indices even on preprocessors with low maximum expansion depths.
 										</div>
 										<div>
 											Elements of a <i>seq</i> can be extracted with <b>BOOST_PP_SEQ_ELEM</b>.
 										</div>
 										<h4>
 											Primitives
 										</h4>
-												preliminary set support


[SVN r15908]

											
										
										
											2002-10-13 05:47:23 +00:00
+										<ul>
-												set -> seq


[SVN r16150]

											
										
										
											2002-11-07 23:39:29 +00:00
+											<li>
 												<a href="../ref/seq_elem.html">BOOST_PP_SEQ_ELEM</a></li>
-												preliminary set support


[SVN r15908]

											
										
										
											2002-10-13 05:47:23 +00:00
+										</ul>
-												Fix various inspection errors: add missing copyright and license info.


[SVN r34683]

											
										
										
											2006-07-23 20:45:18 +00:00
+									<hr size="1">
 									<div style="margin-left: 0px;">
 										<i><EFBFBD> Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
-												After asking Paul... add his copyright to the docs.


[SVN r34691]

											
										
										
											2006-07-24 04:08:25 +00:00
+										</br><i><EFBFBD> Copyright Paul Mensonides 2002</i>
-												Fix various inspection errors: add missing copyright and license info.


[SVN r34683]

											
										
										
											2006-07-23 20:45:18 +00:00
+									</div>
 									<div style="margin-left: 0px;">
 										<p><small>Distributed under the Boost Software License, Version 1.0. (See
 										accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
 										copy at <a href=
 										"http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
 									</div>
-												set -> seq


[SVN r16150]

											
										
										
											2002-11-07 23:39:29 +00:00
+									</body>
-												preliminary set support


[SVN r15908]

											
										
										
											2002-10-13 05:47:23 +00:00
+								</html>