1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Forward Sequence</title> 5<link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../../index.html" title="Chapter 1. Fusion 2.2"> 8<link rel="up" href="../concepts.html" title="Concepts"> 9<link rel="prev" href="../concepts.html" title="Concepts"> 10<link rel="next" href="bidirectional_sequence.html" title="Bidirectional Sequence"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr> 14<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../../boost.png"></td> 15<td align="center"><a href="../../../../../../../index.html">Home</a></td> 16<td align="center"><a href="../../../../../../../libs/libraries.htm">Libraries</a></td> 17<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 18<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 19<td align="center"><a href="../../../../../../../more/index.htm">More</a></td> 20</tr></table> 21<hr> 22<div class="spirit-nav"> 23<a accesskey="p" href="../concepts.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../concepts.html"><img src="../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="bidirectional_sequence.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h4 class="title"> 27<a name="fusion.sequence.concepts.forward_sequence"></a><a class="link" href="forward_sequence.html" title="Forward Sequence">Forward 28 Sequence</a> 29</h4></div></div></div> 30<h6> 31<a name="fusion.sequence.concepts.forward_sequence.h0"></a> 32 <span class="phrase"><a name="fusion.sequence.concepts.forward_sequence.description"></a></span><a class="link" href="forward_sequence.html#fusion.sequence.concepts.forward_sequence.description">Description</a> 33 </h6> 34<p> 35 A Forward Sequence is a Sequence whose elements are arranged in a definite 36 order. The ordering is guaranteed not to change from iteration to iteration. 37 The requirement of a definite ordering allows the definition of element-by-element 38 equality (if the container's element type is Equality Comparable) and of 39 lexicographical ordering (if the container's element type is LessThan Comparable). 40 </p> 41<div class="variablelist"> 42<p class="title"><b>Notation</b></p> 43<dl class="variablelist"> 44<dt><span class="term"><code class="computeroutput"><span class="identifier">s</span></code></span></dt> 45<dd><p> 46 A Forward Sequence 47 </p></dd> 48<dt><span class="term"><code class="computeroutput"><span class="identifier">S</span></code></span></dt> 49<dd><p> 50 A Forward Sequence type 51 </p></dd> 52<dt><span class="term"><code class="computeroutput"><span class="identifier">o</span></code></span></dt> 53<dd><p> 54 An arbitrary object 55 </p></dd> 56<dt><span class="term"><code class="computeroutput"><span class="identifier">e</span></code></span></dt> 57<dd><p> 58 A Sequence element 59 </p></dd> 60</dl> 61</div> 62<h6> 63<a name="fusion.sequence.concepts.forward_sequence.h1"></a> 64 <span class="phrase"><a name="fusion.sequence.concepts.forward_sequence.valid_expressions"></a></span><a class="link" href="forward_sequence.html#fusion.sequence.concepts.forward_sequence.valid_expressions">Valid 65 Expressions</a> 66 </h6> 67<p> 68 For any Forward Sequence the following expressions must be valid: 69 </p> 70<div class="informaltable"><table class="table"> 71<colgroup> 72<col> 73<col> 74<col> 75<col> 76</colgroup> 77<thead><tr> 78<th> 79 <p> 80 Expression 81 </p> 82 </th> 83<th> 84 <p> 85 Return type 86 </p> 87 </th> 88<th> 89 <p> 90 Type Requirements 91 </p> 92 </th> 93<th> 94 <p> 95 Runtime Complexity 96 </p> 97 </th> 98</tr></thead> 99<tbody> 100<tr> 101<td> 102 <p> 103 <code class="computeroutput"><a class="link" href="../intrinsic/functions/begin.html" title="begin"><code class="computeroutput"><span class="identifier">begin</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code> 104 </p> 105 </td> 106<td> 107 <p> 108 <a class="link" href="../../iterator/concepts/forward_iterator.html" title="Forward Iterator">Forward 109 Iterator</a> 110 </p> 111 </td> 112<td> 113 </td> 114<td> 115 <p> 116 Constant 117 </p> 118 </td> 119</tr> 120<tr> 121<td> 122 <p> 123 <code class="computeroutput"><a class="link" href="../intrinsic/functions/end.html" title="end"><code class="computeroutput"><span class="identifier">end</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code> 124 </p> 125 </td> 126<td> 127 <p> 128 <a class="link" href="../../iterator/concepts/forward_iterator.html" title="Forward Iterator">Forward 129 Iterator</a> 130 </p> 131 </td> 132<td> 133 </td> 134<td> 135 <p> 136 Constant 137 </p> 138 </td> 139</tr> 140<tr> 141<td> 142 <p> 143 <code class="computeroutput"><a class="link" href="../intrinsic/functions/size.html" title="size"><code class="computeroutput"><span class="identifier">size</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code> 144 </p> 145 </td> 146<td> 147 <p> 148 <a href="http://www.boost.org/libs/mpl/doc/refmanual/integral-constant.html" target="_top">MPL 149 Integral Constant</a>. Convertible to int. 150 </p> 151 </td> 152<td> 153 </td> 154<td> 155 <p> 156 Constant 157 </p> 158 </td> 159</tr> 160<tr> 161<td> 162 <p> 163 <code class="computeroutput"><a class="link" href="../intrinsic/functions/empty.html" title="empty"><code class="computeroutput"><span class="identifier">empty</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code> 164 </p> 165 </td> 166<td> 167 <p> 168 <a href="http://www.boost.org/libs/mpl/doc/refmanual/integral-constant.html" target="_top">MPL 169 Boolean Constant</a>. Convertible to bool. 170 </p> 171 </td> 172<td> 173 </td> 174<td> 175 <p> 176 Constant 177 </p> 178 </td> 179</tr> 180<tr> 181<td> 182 <p> 183 <code class="computeroutput"><a class="link" href="../intrinsic/functions/front.html" title="front"><code class="computeroutput"><span class="identifier">front</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code> 184 </p> 185 </td> 186<td> 187 <p> 188 Any type 189 </p> 190 </td> 191<td> 192 </td> 193<td> 194 <p> 195 Constant 196 </p> 197 </td> 198</tr> 199<tr> 200<td> 201 <p> 202 <code class="computeroutput"><a class="link" href="../intrinsic/functions/front.html" title="front"><code class="computeroutput"><span class="identifier">front</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span> 203 <span class="special">=</span> <span class="identifier">o</span></code> 204 </p> 205 </td> 206<td> 207 <p> 208 Any type 209 </p> 210 </td> 211<td> 212 <p> 213 <code class="computeroutput"><span class="identifier">s</span></code> is mutable 214 and <code class="computeroutput"><span class="identifier">e</span> <span class="special">=</span> 215 <span class="identifier">o</span></code>, where <code class="computeroutput"><span class="identifier">e</span></code> is the first element in the 216 sequence, is a valid expression. 217 </p> 218 </td> 219<td> 220 <p> 221 Constant 222 </p> 223 </td> 224</tr> 225</tbody> 226</table></div> 227<h6> 228<a name="fusion.sequence.concepts.forward_sequence.h2"></a> 229 <span class="phrase"><a name="fusion.sequence.concepts.forward_sequence.result_type_expressions"></a></span><a class="link" href="forward_sequence.html#fusion.sequence.concepts.forward_sequence.result_type_expressions">Result 230 Type Expressions</a> 231 </h6> 232<div class="informaltable"><table class="table"> 233<colgroup> 234<col> 235<col> 236</colgroup> 237<thead><tr> 238<th> 239 <p> 240 Expression 241 </p> 242 </th> 243<th> 244 <p> 245 Compile Time Complexity 246 </p> 247 </th> 248</tr></thead> 249<tbody> 250<tr> 251<td> 252 <p> 253 <code class="computeroutput"><a class="link" href="../intrinsic/metafunctions/begin.html" title="begin"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">begin</span></code></a><span class="special"><</span><span class="identifier">S</span><span class="special">>::</span><span class="identifier">type</span></code> 254 </p> 255 </td> 256<td> 257 <p> 258 Amortized constant time 259 </p> 260 </td> 261</tr> 262<tr> 263<td> 264 <p> 265 <code class="computeroutput"><a class="link" href="../intrinsic/metafunctions/end.html" title="end"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">end</span></code></a><span class="special"><</span><span class="identifier">S</span><span class="special">>::</span><span class="identifier">type</span></code> 266 </p> 267 </td> 268<td> 269 <p> 270 Amortized constant time 271 </p> 272 </td> 273</tr> 274<tr> 275<td> 276 <p> 277 <code class="computeroutput"><a class="link" href="../intrinsic/metafunctions/size.html" title="size"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">size</span></code></a><span class="special"><</span><span class="identifier">S</span><span class="special">>::</span><span class="identifier">type</span></code> 278 </p> 279 </td> 280<td> 281 <p> 282 Unspecified 283 </p> 284 </td> 285</tr> 286<tr> 287<td> 288 <p> 289 <code class="computeroutput"><a class="link" href="../intrinsic/metafunctions/empty.html" title="empty"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">empty</span></code></a><span class="special"><</span><span class="identifier">S</span><span class="special">>::</span><span class="identifier">type</span></code> 290 </p> 291 </td> 292<td> 293 <p> 294 Constant time 295 </p> 296 </td> 297</tr> 298<tr> 299<td> 300 <p> 301 <code class="computeroutput"><a class="link" href="../intrinsic/metafunctions/front.html" title="front"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">front</span></code></a><span class="special"><</span><span class="identifier">S</span><span class="special">>::</span><span class="identifier">type</span></code> 302 </p> 303 </td> 304<td> 305 <p> 306 Amortized constant time 307 </p> 308 </td> 309</tr> 310</tbody> 311</table></div> 312<h6> 313<a name="fusion.sequence.concepts.forward_sequence.h3"></a> 314 <span class="phrase"><a name="fusion.sequence.concepts.forward_sequence.expression_semantics"></a></span><a class="link" href="forward_sequence.html#fusion.sequence.concepts.forward_sequence.expression_semantics">Expression 315 Semantics</a> 316 </h6> 317<div class="informaltable"><table class="table"> 318<colgroup> 319<col> 320<col> 321</colgroup> 322<thead><tr> 323<th> 324 <p> 325 Expression 326 </p> 327 </th> 328<th> 329 <p> 330 Semantics 331 </p> 332 </th> 333</tr></thead> 334<tbody> 335<tr> 336<td> 337 <p> 338 <code class="computeroutput"><a class="link" href="../intrinsic/functions/begin.html" title="begin"><code class="computeroutput"><span class="identifier">begin</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code> 339 </p> 340 </td> 341<td> 342 <p> 343 An iterator to the first element of the sequence; see <a class="link" href="../intrinsic/functions/begin.html" title="begin"><code class="computeroutput"><span class="identifier">begin</span></code></a>. 344 </p> 345 </td> 346</tr> 347<tr> 348<td> 349 <p> 350 <code class="computeroutput"><a class="link" href="../intrinsic/functions/end.html" title="end"><code class="computeroutput"><span class="identifier">end</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code> 351 </p> 352 </td> 353<td> 354 <p> 355 A past-the-end iterator to the sequence; see <a class="link" href="../intrinsic/functions/end.html" title="end"><code class="computeroutput"><span class="identifier">end</span></code></a>. 356 </p> 357 </td> 358</tr> 359<tr> 360<td> 361 <p> 362 <code class="computeroutput"><a class="link" href="../intrinsic/functions/size.html" title="size"><code class="computeroutput"><span class="identifier">size</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code> 363 </p> 364 </td> 365<td> 366 <p> 367 The size of the sequence; see <a class="link" href="../intrinsic/functions/size.html" title="size"><code class="computeroutput"><span class="identifier">size</span></code></a>. 368 </p> 369 </td> 370</tr> 371<tr> 372<td> 373 <p> 374 <code class="computeroutput"><a class="link" href="../intrinsic/functions/empty.html" title="empty"><code class="computeroutput"><span class="identifier">empty</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code> 375 </p> 376 </td> 377<td> 378 <p> 379 A boolean Integral Constant <code class="computeroutput"><span class="identifier">c</span></code> 380 such that <code class="computeroutput"><span class="identifier">c</span><span class="special">::</span><span class="identifier">value</span> <span class="special">==</span> 381 <span class="keyword">true</span></code> if and only if the 382 sequence is empty; see <a class="link" href="../intrinsic/functions/empty.html" title="empty"><code class="computeroutput"><span class="identifier">empty</span></code></a>. 383 </p> 384 </td> 385</tr> 386<tr> 387<td> 388 <p> 389 <code class="computeroutput"><a class="link" href="../intrinsic/functions/front.html" title="front"><code class="computeroutput"><span class="identifier">front</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code> 390 </p> 391 </td> 392<td> 393 <p> 394 The first element in the sequence; see <a class="link" href="../intrinsic/functions/front.html" title="front"><code class="computeroutput"><span class="identifier">front</span></code></a>. 395 </p> 396 </td> 397</tr> 398</tbody> 399</table></div> 400<h6> 401<a name="fusion.sequence.concepts.forward_sequence.h4"></a> 402 <span class="phrase"><a name="fusion.sequence.concepts.forward_sequence.invariants"></a></span><a class="link" href="forward_sequence.html#fusion.sequence.concepts.forward_sequence.invariants">Invariants</a> 403 </h6> 404<p> 405 For any Forward Sequence s the following invariants always hold: 406 </p> 407<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 408<li class="listitem"> 409 <code class="computeroutput"><span class="special">[</span><a class="link" href="../intrinsic/functions/begin.html" title="begin"><code class="computeroutput"><span class="identifier">begin</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">),</span> <a class="link" href="../intrinsic/functions/end.html" title="end"><code class="computeroutput"><span class="identifier">end</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">))</span></code> is always a valid range. 410 </li> 411<li class="listitem"> 412 An <a class="link" href="../../algorithm.html" title="Algorithm">Algorithm</a> that iterates 413 through the range <code class="computeroutput"><span class="special">[</span><a class="link" href="../intrinsic/functions/begin.html" title="begin"><code class="computeroutput"><span class="identifier">begin</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">),</span> <a class="link" href="../intrinsic/functions/end.html" title="end"><code class="computeroutput"><span class="identifier">end</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">))</span></code> will pass through every element of 414 <code class="computeroutput"><span class="identifier">s</span></code> exactly once. 415 </li> 416<li class="listitem"> 417 <code class="computeroutput"><a class="link" href="../intrinsic/functions/begin.html" title="begin"><code class="computeroutput"><span class="identifier">begin</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code> 418 is identical to <code class="computeroutput"><a class="link" href="../intrinsic/functions/end.html" title="end"><code class="computeroutput"><span class="identifier">end</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">))</span></code> 419 if and only if <code class="computeroutput"><span class="identifier">s</span></code> is 420 empty. 421 </li> 422<li class="listitem"> 423 Two different iterations through <code class="computeroutput"><span class="identifier">s</span></code> 424 will access its elements in the same order. 425 </li> 426</ul></div> 427<h6> 428<a name="fusion.sequence.concepts.forward_sequence.h5"></a> 429 <span class="phrase"><a name="fusion.sequence.concepts.forward_sequence.models"></a></span><a class="link" href="forward_sequence.html#fusion.sequence.concepts.forward_sequence.models">Models</a> 430 </h6> 431<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 432<li class="listitem"> 433 <a class="link" href="../../adapted/std__pair.html" title="std::pair"><code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span></code></a> 434 </li> 435<li class="listitem"> 436 <a class="link" href="../../adapted/boost__array.html" title="boost::array"><code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">array</span></code></a> 437 </li> 438<li class="listitem"> 439 <a class="link" href="../../container/vector.html" title="vector"><code class="computeroutput"><span class="identifier">vector</span></code></a> 440 </li> 441<li class="listitem"> 442 <a class="link" href="../../container/cons.html" title="cons"><code class="computeroutput"><span class="identifier">cons</span></code></a> 443 </li> 444<li class="listitem"> 445 <a class="link" href="../../container/list.html" title="list"><code class="computeroutput"><span class="identifier">list</span></code></a> 446 </li> 447<li class="listitem"> 448 <a class="link" href="../../container/set.html" title="set"><code class="computeroutput"><span class="identifier">set</span></code></a> 449 </li> 450<li class="listitem"> 451 <a class="link" href="../../container/map.html" title="map"><code class="computeroutput"><span class="identifier">map</span></code></a> 452 </li> 453<li class="listitem"> 454 <a class="link" href="../../view/single_view.html" title="single_view"><code class="computeroutput"><span class="identifier">single_view</span></code></a> 455 </li> 456<li class="listitem"> 457 <a class="link" href="../../view/filter_view.html" title="filter_view"><code class="computeroutput"><span class="identifier">filter_view</span></code></a> 458 </li> 459<li class="listitem"> 460 <a class="link" href="../../view/iterator_range.html" title="iterator_range"><code class="computeroutput"><span class="identifier">iterator_range</span></code></a> 461 </li> 462<li class="listitem"> 463 <a class="link" href="../../view/joint_view.html" title="joint_view"><code class="computeroutput"><span class="identifier">joint_view</span></code></a> 464 </li> 465<li class="listitem"> 466 <a class="link" href="../../view/transform_view.html" title="transform_view"><code class="computeroutput"><span class="identifier">transform_view</span></code></a> 467 </li> 468<li class="listitem"> 469 <a class="link" href="../../view/reverse_view.html" title="reverse_view"><code class="computeroutput"><span class="identifier">reverse_view</span></code></a> 470 </li> 471<li class="listitem"> 472 <a class="link" href="../../view/zip_view.html" title="zip_view"><code class="computeroutput"><span class="identifier">zip_view</span></code></a> 473 </li> 474</ul></div> 475</div> 476<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 477<td align="left"></td> 478<td align="right"><div class="copyright-footer">Copyright © 2001-2006, 2011, 2012 Joel de Guzman, 479 Dan Marsden, Tobias Schwinger<p> 480 Distributed under the Boost Software License, Version 1.0. (See accompanying 481 file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) 482 </p> 483</div></td> 484</tr></table> 485<hr> 486<div class="spirit-nav"> 487<a accesskey="p" href="../concepts.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../concepts.html"><img src="../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="bidirectional_sequence.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> 488</div> 489</body> 490</html> 491
