1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Functions</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. Range 2.0"> 8<link rel="up" href="../semantics.html" title="Semantics"> 9<link rel="prev" href="metafunctions.html" title="Metafunctions"> 10<link rel="next" href="../../adaptors.html" title="Range Adaptors"> 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="metafunctions.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../semantics.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="../../adaptors.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h5 class="title"> 27<a name="range.reference.concept_implementation.semantics.functions"></a><a class="link" href="functions.html" title="Functions">Functions</a> 28</h5></div></div></div> 29<div class="informaltable"><table class="table"> 30<colgroup> 31<col> 32<col> 33<col> 34</colgroup> 35<thead><tr> 36<th> 37 <p> 38 Expression 39 </p> 40 </th> 41<th> 42 <p> 43 Return type 44 </p> 45 </th> 46<th> 47 <p> 48 Returns 49 </p> 50 </th> 51<th> 52 <p> 53 Complexity 54 </p> 55 </th> 56</tr></thead> 57<tbody> 58<tr> 59<td> 60 <p> 61 <code class="computeroutput"><span class="identifier">begin</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> 62 </p> 63 </td> 64<td> 65 <p> 66 <code class="computeroutput"><span class="identifier">range_iterator</span><span class="special"><</span><span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span></code> 67 </p> 68 </td> 69<td> 70 <p> 71 <code class="computeroutput"><span class="identifier">p</span><span class="special">.</span><span class="identifier">first</span></code> if <code class="computeroutput"><span class="identifier">p</span></code> 72 is of type <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span></code> <code class="computeroutput"><span class="identifier">a</span></code> 73 if <code class="computeroutput"><span class="identifier">a</span></code> is an 74 array <code class="computeroutput"><span class="identifier">range_begin</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> if that expression would invoke 75 a function found by ADL <code class="computeroutput"><span class="identifier">t</span><span class="special">.</span><span class="identifier">begin</span><span class="special">()</span></code> otherwise 76 </p> 77 </td> 78<td> 79 <p> 80 constant time 81 </p> 82 </td> 83</tr> 84<tr> 85<td> 86 <p> 87 <code class="computeroutput"><span class="identifier">end</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> 88 </p> 89 </td> 90<td> 91 <p> 92 <code class="computeroutput"><span class="identifier">range_iterator</span><span class="special"><</span><span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span></code> 93 </p> 94 </td> 95<td> 96 <p> 97 <code class="computeroutput"><span class="identifier">p</span><span class="special">.</span><span class="identifier">second</span></code> if <code class="computeroutput"><span class="identifier">p</span></code> 98 is of type <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span></code> <code class="computeroutput"><span class="identifier">a</span> 99 <span class="special">+</span> <span class="identifier">sz</span></code> 100 if <code class="computeroutput"><span class="identifier">a</span></code> is an 101 array of size <code class="computeroutput"><span class="identifier">sz</span></code> 102 <code class="computeroutput"><span class="identifier">range_end</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> 103 if that expression would invoke a function found by ADL <code class="computeroutput"><span class="identifier">t</span><span class="special">.</span><span class="identifier">end</span><span class="special">()</span></code> 104 otherwise 105 </p> 106 </td> 107<td> 108 <p> 109 constant time 110 </p> 111 </td> 112</tr> 113<tr> 114<td> 115 <p> 116 <code class="computeroutput"><span class="identifier">empty</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> 117 </p> 118 </td> 119<td> 120 <p> 121 <code class="computeroutput"><span class="keyword">bool</span></code> 122 </p> 123 </td> 124<td> 125 <p> 126 <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">begin</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span> 127 <span class="special">==</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">end</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> 128 </p> 129 </td> 130<td> 131 <p> 132 constant time 133 </p> 134 </td> 135</tr> 136<tr> 137<td> 138 <p> 139 <code class="computeroutput"><span class="identifier">distance</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> 140 </p> 141 </td> 142<td> 143 <p> 144 <code class="computeroutput"><span class="identifier">range_difference</span><span class="special"><</span><span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span></code> 145 </p> 146 </td> 147<td> 148 <p> 149 <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">distance</span><span class="special">(</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">begin</span><span class="special">(</span><span class="identifier">x</span><span class="special">),</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">end</span><span class="special">(</span><span class="identifier">x</span><span class="special">))</span></code> 150 </p> 151 </td> 152<td> 153 <p> 154 - 155 </p> 156 </td> 157</tr> 158<tr> 159<td> 160 <p> 161 <code class="computeroutput"><span class="identifier">size</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> 162 </p> 163 </td> 164<td> 165 <p> 166 <code class="computeroutput"><span class="identifier">range_size</span><span class="special"><</span><span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span></code> 167 </p> 168 </td> 169<td> 170 <p> 171 <code class="computeroutput"><span class="identifier">range_calculate_size</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> which by default is <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">end</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span> 172 <span class="special">-</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">begin</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code>. Users may supply alternative 173 implementations by implementing <code class="computeroutput"><span class="identifier">range_calculate_size</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> so that it will be found via 174 ADL 175 </p> 176 </td> 177<td> 178 <p> 179 constant time 180 </p> 181 </td> 182</tr> 183<tr> 184<td> 185 <p> 186 <code class="computeroutput"><span class="identifier">rbegin</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> 187 </p> 188 </td> 189<td> 190 <p> 191 <code class="computeroutput"><span class="identifier">range_reverse_iterator</span><span class="special"><</span><span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span></code> 192 </p> 193 </td> 194<td> 195 <p> 196 <code class="computeroutput"><span class="identifier">range_reverse_iterator</span><span class="special"><</span><span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span><span class="special">(</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">end</span><span class="special">(</span><span class="identifier">x</span><span class="special">))</span></code> 197 </p> 198 </td> 199<td> 200 <p> 201 constant time 202 </p> 203 </td> 204</tr> 205<tr> 206<td> 207 <p> 208 <code class="computeroutput"><span class="identifier">rend</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> 209 </p> 210 </td> 211<td> 212 <p> 213 <code class="computeroutput"><span class="identifier">range_reverse_iterator</span><span class="special"><</span><span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span></code> 214 </p> 215 </td> 216<td> 217 <p> 218 <code class="computeroutput"><span class="identifier">range_reverse_iterator</span><span class="special"><</span><span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span><span class="special">(</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">begin</span><span class="special">(</span><span class="identifier">x</span><span class="special">))</span></code> 219 </p> 220 </td> 221<td> 222 <p> 223 constant time 224 </p> 225 </td> 226</tr> 227<tr> 228<td> 229 <p> 230 <code class="computeroutput"><span class="identifier">const_begin</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> 231 </p> 232 </td> 233<td> 234 <p> 235 <code class="computeroutput"><span class="identifier">range_iterator</span><span class="special"><</span><span class="keyword">const</span> 236 <span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span></code> 237 </p> 238 </td> 239<td> 240 <p> 241 <code class="computeroutput"><span class="identifier">range_iterator</span><span class="special"><</span><span class="keyword">const</span> 242 <span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span><span class="special">(</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">begin</span><span class="special">(</span><span class="identifier">x</span><span class="special">))</span></code> 243 </p> 244 </td> 245<td> 246 <p> 247 constant time 248 </p> 249 </td> 250</tr> 251<tr> 252<td> 253 <p> 254 <code class="computeroutput"><span class="identifier">const_end</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> 255 </p> 256 </td> 257<td> 258 <p> 259 <code class="computeroutput"><span class="identifier">range_iterator</span><span class="special"><</span><span class="keyword">const</span> 260 <span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span></code> 261 </p> 262 </td> 263<td> 264 <p> 265 <code class="computeroutput"><span class="identifier">range_iterator</span><span class="special"><</span><span class="keyword">const</span> 266 <span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span><span class="special">(</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">end</span><span class="special">(</span><span class="identifier">x</span><span class="special">))</span></code> 267 </p> 268 </td> 269<td> 270 <p> 271 constant time 272 </p> 273 </td> 274</tr> 275<tr> 276<td> 277 <p> 278 <code class="computeroutput"><span class="identifier">const_rbegin</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> 279 </p> 280 </td> 281<td> 282 <p> 283 <code class="computeroutput"><span class="identifier">range_reverse_iterator</span><span class="special"><</span><span class="keyword">const</span> 284 <span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span></code> 285 </p> 286 </td> 287<td> 288 <p> 289 <code class="computeroutput"><span class="identifier">range_reverse_iterator</span><span class="special"><</span><span class="keyword">const</span> 290 <span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span><span class="special">(</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">rbegin</span><span class="special">(</span><span class="identifier">x</span><span class="special">))</span></code> 291 </p> 292 </td> 293<td> 294 <p> 295 constant time 296 </p> 297 </td> 298</tr> 299<tr> 300<td> 301 <p> 302 <code class="computeroutput"><span class="identifier">const_rend</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> 303 </p> 304 </td> 305<td> 306 <p> 307 <code class="computeroutput"><span class="identifier">range_reverse_iterator</span><span class="special"><</span><span class="keyword">const</span> 308 <span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span></code> 309 </p> 310 </td> 311<td> 312 <p> 313 <code class="computeroutput"><span class="identifier">range_reverse_iterator</span><span class="special"><</span><span class="keyword">const</span> 314 <span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span><span class="special">(</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">rend</span><span class="special">(</span><span class="identifier">x</span><span class="special">))</span></code> 315 </p> 316 </td> 317<td> 318 <p> 319 constant time 320 </p> 321 </td> 322</tr> 323<tr> 324<td> 325 <p> 326 <code class="computeroutput"><span class="identifier">as_literal</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> 327 </p> 328 </td> 329<td> 330 <p> 331 <code class="computeroutput"><span class="identifier">iterator_range</span><span class="special"><</span><span class="identifier">U</span><span class="special">></span></code> where <code class="computeroutput"><span class="identifier">U</span></code> 332 is <code class="computeroutput"><span class="identifier">Char</span><span class="special">*</span></code> 333 if <code class="computeroutput"><span class="identifier">x</span></code> is a pointer 334 to a string and <code class="computeroutput"><span class="identifier">U</span></code> 335 is <code class="computeroutput"><span class="identifier">range_iterator</span><span class="special"><</span><span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span></code> 336 otherwise 337 </p> 338 </td> 339<td> 340 <p> 341 <code class="computeroutput"><span class="special">[</span><span class="identifier">s</span><span class="special">,</span><span class="identifier">s</span> 342 <span class="special">+</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">char_traits</span><span class="special"><</span><span class="identifier">X</span><span class="special">>::</span><span class="identifier">length</span><span class="special">(</span><span class="identifier">s</span><span class="special">))</span></code> if <code class="computeroutput"><span class="identifier">s</span></code> 343 is a <code class="computeroutput"><span class="identifier">Char</span><span class="special">*</span></code> 344 or an array of <code class="computeroutput"><span class="identifier">Char</span></code> 345 <code class="computeroutput"><span class="special">[</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">begin</span><span class="special">(</span><span class="identifier">x</span><span class="special">),</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">end</span><span class="special">(</span><span class="identifier">x</span><span class="special">))</span></code> otherwise 346 </p> 347 </td> 348<td> 349 <p> 350 linear time for pointers to a string or arrays of <code class="computeroutput"><span class="identifier">Char</span></code>, constant time otherwise 351 </p> 352 </td> 353</tr> 354<tr> 355<td> 356 <p> 357 <code class="computeroutput"><span class="identifier">as_array</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code> 358 </p> 359 </td> 360<td> 361 <p> 362 <code class="computeroutput"><span class="identifier">iterator_range</span><span class="special"><</span><span class="identifier">X</span><span class="special">></span></code> 363 </p> 364 </td> 365<td> 366 <p> 367 <code class="computeroutput"><span class="special">[</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">begin</span><span class="special">(</span><span class="identifier">x</span><span class="special">),</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">end</span><span class="special">(</span><span class="identifier">x</span><span class="special">))</span></code> 368 </p> 369 </td> 370</tr> 371</tbody> 372</table></div> 373<p> 374 The special <code class="computeroutput"><span class="identifier">const_</span></code>-named 375 functions are useful when you want to document clearly that your code 376 is read-only. 377 </p> 378<p> 379 <code class="computeroutput"><span class="identifier">as_literal</span><span class="special">()</span></code> 380 can be used <span class="emphasis"><em><span class="bold"><strong>internally</strong></span></em></span> 381 in string algorithm libraries such that arrays of characters are handled 382 correctly. 383 </p> 384<p> 385 <code class="computeroutput"><span class="identifier">as_array</span><span class="special">()</span></code> 386 can be used with string algorithm libraries to make it clear that arrays 387 of characters are handled like an array and not like a string. 388 </p> 389<p> 390 Notice that the above functions should always be called with qualification 391 (<code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span></code>) 392 to prevent <span class="emphasis"><em><span class="bold"><strong>unintended</strong></span></em></span> 393 Argument Dependent Lookup (ADL). 394 </p> 395</div> 396<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 397<td align="left"></td> 398<td align="right"><div class="copyright-footer">Copyright © 2003-2010 Thorsten Ottosen, 399 Neil Groves<p> 400 Distributed under the Boost Software License, Version 1.0. (See accompanying 401 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>) 402 </p> 403</div></td> 404</tr></table> 405<hr> 406<div class="spirit-nav"> 407<a accesskey="p" href="metafunctions.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../semantics.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="../../adaptors.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 408</div> 409</body> 410</html> 411
