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  26 <div class="titlepage"><div><div><h3 class="title">
  27 <a name="boost_regex.syntax.basic_extended"></a><a class="link" href="basic_extended.html" title="POSIX Extended Regular Expression Syntax">POSIX Extended Regular
  28       Expression Syntax</a>
  29 </h3></div></div></div>
  30 <h4>
  31 <a name="boost_regex.syntax.basic_extended.h0"></a>
  32         <span class="phrase"><a name="boost_regex.syntax.basic_extended.synopsis"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.synopsis">Synopsis</a>
  33       </h4>
  34 <p>
  35         The POSIX-Extended regular expression syntax is supported by the POSIX C
  36         regular expression API's, and variations are used by the utilities <code class="computeroutput"><span class="identifier">egrep</span></code> and <code class="computeroutput"><span class="identifier">awk</span></code>.
  37         You can construct POSIX extended regular expressions in Boost.Regex by passing
  38         the flag <code class="computeroutput"><span class="identifier">extended</span></code> to the
  39         regex constructor, for example:
  40       </p>
  41 <pre class="programlisting"><span class="comment">// e1 is a case sensitive POSIX-Extended expression:</span>
  42 <span class="identifier">boost</span><span class="special">::</span><span class="identifier">regex</span> <span class="identifier">e1</span><span class="special">(</span><span class="identifier">my_expression</span><span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">regex</span><span class="special">::</span><span class="identifier">extended</span><span class="special">);</span>
  43 <span class="comment">// e2 a case insensitive POSIX-Extended expression:</span>
  44 <span class="identifier">boost</span><span class="special">::</span><span class="identifier">regex</span> <span class="identifier">e2</span><span class="special">(</span><span class="identifier">my_expression</span><span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">regex</span><span class="special">::</span><span class="identifier">extended</span><span class="special">|</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">regex</span><span class="special">::</span><span class="identifier">icase</span><span class="special">);</span>
  45 </pre>
  46 <a name="boost_regex.posix_extended_syntax"></a><h4>
  47 <a name="boost_regex.syntax.basic_extended.h1"></a>
  48         <span class="phrase"><a name="boost_regex.syntax.basic_extended.posix_extended_syntax"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.posix_extended_syntax">POSIX Extended
  49         Syntax</a>
  50       </h4>
  51 <p>
  52         In POSIX-Extended regular expressions, all characters match themselves except
  53         for the following special characters:
  54       </p>
  55 <pre class="programlisting">.[{}()\*+?|^$</pre>
  56 <h5>
  57 <a name="boost_regex.syntax.basic_extended.h2"></a>
  58         <span class="phrase"><a name="boost_regex.syntax.basic_extended.wildcard"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.wildcard">Wildcard:</a>
  59       </h5>
  60 <p>
  61         The single character '.' when used outside of a character set will match
  62         any single character except:
  63       </p>
  64 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
  65 <li class="listitem">
  66             The NULL character when the flag <code class="computeroutput"><span class="identifier">match_no_dot_null</span></code>
  67             is passed to the matching algorithms.
  68           </li>
  69 <li class="listitem">
  70             The newline character when the flag <code class="computeroutput"><span class="identifier">match_not_dot_newline</span></code>
  71             is passed to the matching algorithms.
  72           </li>
  73 </ul></div>
  74 <h5>
  75 <a name="boost_regex.syntax.basic_extended.h3"></a>
  76         <span class="phrase"><a name="boost_regex.syntax.basic_extended.anchors"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.anchors">Anchors:</a>
  77       </h5>
  78 <p>
  79         A '^' character shall match the start of a line when used as the first character
  80         of an expression, or the first character of a sub-expression.
  81       </p>
  82 <p>
  83         A '$' character shall match the end of a line when used as the last character
  84         of an expression, or the last character of a sub-expression.
  85       </p>
  86 <h5>
  87 <a name="boost_regex.syntax.basic_extended.h4"></a>
  88         <span class="phrase"><a name="boost_regex.syntax.basic_extended.marked_sub_expressions"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.marked_sub_expressions">Marked
  89         sub-expressions:</a>
  90       </h5>
  91 <p>
  92         A section beginning <code class="computeroutput"><span class="special">(</span></code> and ending
  93         <code class="computeroutput"><span class="special">)</span></code> acts as a marked sub-expression.
  94         Whatever matched the sub-expression is split out in a separate field by the
  95         matching algorithms. Marked sub-expressions can also repeated, or referred
  96         to by a back-reference.
  97       </p>
  98 <h5>
  99 <a name="boost_regex.syntax.basic_extended.h5"></a>
 100         <span class="phrase"><a name="boost_regex.syntax.basic_extended.repeats"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.repeats">Repeats:</a>
 101       </h5>
 102 <p>
 103         Any atom (a single character, a marked sub-expression, or a character class)
 104         can be repeated with the <code class="computeroutput"><span class="special">*</span></code>,
 105         <code class="computeroutput"><span class="special">+</span></code>, <code class="computeroutput"><span class="special">?</span></code>,
 106         and <code class="computeroutput"><span class="special">{}</span></code> operators.
 107       </p>
 108 <p>
 109         The <code class="computeroutput"><span class="special">*</span></code> operator will match the
 110         preceding atom <span class="emphasis"><em>zero or more times</em></span>, for example the expression
 111         <code class="computeroutput"><span class="identifier">a</span><span class="special">*</span><span class="identifier">b</span></code> will match any of the following:
 112       </p>
 113 <pre class="programlisting">b
 114 ab
 115 aaaaaaaab
 116 </pre>
 117 <p>
 118         The <code class="computeroutput"><span class="special">+</span></code> operator will match the
 119         preceding atom <span class="emphasis"><em>one or more times</em></span>, for example the expression
 120         a+b will match any of the following:
 121       </p>
 122 <pre class="programlisting">ab
 123 aaaaaaaab
 124 </pre>
 125 <p>
 126         But will not match:
 127       </p>
 128 <pre class="programlisting">b
 129 </pre>
 130 <p>
 131         The <code class="computeroutput"><span class="special">?</span></code> operator will match the
 132         preceding atom <span class="emphasis"><em>zero or one times</em></span>, for example the expression
 133         <code class="computeroutput"><span class="identifier">ca</span><span class="special">?</span><span class="identifier">b</span></code> will match any of the following:
 134       </p>
 135 <pre class="programlisting">cb
 136 cab
 137 </pre>
 138 <p>
 139         But will not match:
 140       </p>
 141 <pre class="programlisting">caab
 142 </pre>
 143 <p>
 144         An atom can also be repeated with a bounded repeat:
 145       </p>
 146 <p>
 147         <code class="computeroutput"><span class="identifier">a</span><span class="special">{</span><span class="identifier">n</span><span class="special">}</span></code> Matches
 148         'a' repeated <span class="emphasis"><em>exactly n times</em></span>.
 149       </p>
 150 <p>
 151         <code class="computeroutput"><span class="identifier">a</span><span class="special">{</span><span class="identifier">n</span><span class="special">,}</span></code> Matches
 152         'a' repeated <span class="emphasis"><em>n or more times</em></span>.
 153       </p>
 154 <p>
 155         <code class="computeroutput"><span class="identifier">a</span><span class="special">{</span><span class="identifier">n</span><span class="special">,</span> <span class="identifier">m</span><span class="special">}</span></code> Matches 'a' repeated <span class="emphasis"><em>between n
 156         and m times inclusive</em></span>.
 157       </p>
 158 <p>
 159         For example:
 160       </p>
 161 <pre class="programlisting">^a{2,3}$</pre>
 162 <p>
 163         Will match either of:
 164       </p>
 165 <pre class="programlisting"><span class="identifier">aa</span>
 166 <span class="identifier">aaa</span>
 167 </pre>
 168 <p>
 169         But neither of:
 170       </p>
 171 <pre class="programlisting"><span class="identifier">a</span>
 172 <span class="identifier">aaaa</span>
 173 </pre>
 174 <p>
 175         It is an error to use a repeat operator, if the preceding construct can not
 176         be repeated, for example:
 177       </p>
 178 <pre class="programlisting"><span class="identifier">a</span><span class="special">(*)</span>
 179 </pre>
 180 <p>
 181         Will raise an error, as there is nothing for the <code class="computeroutput"><span class="special">*</span></code>
 182         operator to be applied to.
 183       </p>
 184 <h5>
 185 <a name="boost_regex.syntax.basic_extended.h6"></a>
 186         <span class="phrase"><a name="boost_regex.syntax.basic_extended.back_references"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.back_references">Back
 187         references:</a>
 188       </h5>
 189 <p>
 190         An escape character followed by a digit <span class="emphasis"><em>n</em></span>, where <span class="emphasis"><em>n</em></span>
 191         is in the range 1-9, matches the same string that was matched by sub-expression
 192         <span class="emphasis"><em>n</em></span>. For example the expression:
 193       </p>
 194 <pre class="programlisting">^(a*)[^a]*\1$</pre>
 195 <p>
 196         Will match the string:
 197       </p>
 198 <pre class="programlisting"><span class="identifier">aaabbaaa</span>
 199 </pre>
 200 <p>
 201         But not the string:
 202       </p>
 203 <pre class="programlisting"><span class="identifier">aaabba</span>
 204 </pre>
 205 <div class="caution"><table border="0" summary="Caution">
 206 <tr>
 207 <td rowspan="2" align="center" valign="top" width="25"><img alt="[Caution]" src="../../../../../../doc/src/images/caution.png"></td>
 208 <th align="left">Caution</th>
 209 </tr>
 210 <tr><td align="left" valign="top"><p>
 211           The POSIX standard does not support back-references for "extended"
 212           regular expressions, this is a compatible extension to that standard.
 213         </p></td></tr>
 214 </table></div>
 215 <h5>
 216 <a name="boost_regex.syntax.basic_extended.h7"></a>
 217         <span class="phrase"><a name="boost_regex.syntax.basic_extended.alternation"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.alternation">Alternation</a>
 218       </h5>
 219 <p>
 220         The <code class="computeroutput"><span class="special">|</span></code> operator will match either
 221         of its arguments, so for example: <code class="computeroutput"><span class="identifier">abc</span><span class="special">|</span><span class="identifier">def</span></code> will
 222         match either "abc" or "def".
 223       </p>
 224 <p>
 225         Parenthesis can be used to group alternations, for example: <code class="computeroutput"><span class="identifier">ab</span><span class="special">(</span><span class="identifier">d</span><span class="special">|</span><span class="identifier">ef</span><span class="special">)</span></code>
 226         will match either of "abd" or "abef".
 227       </p>
 228 <h5>
 229 <a name="boost_regex.syntax.basic_extended.h8"></a>
 230         <span class="phrase"><a name="boost_regex.syntax.basic_extended.character_sets"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.character_sets">Character
 231         sets:</a>
 232       </h5>
 233 <p>
 234         A character set is a bracket-expression starting with [ and ending with ],
 235         it defines a set of characters, and matches any single character that is
 236         a member of that set.
 237       </p>
 238 <p>
 239         A bracket expression may contain any combination of the following:
 240       </p>
 241 <h6>
 242 <a name="boost_regex.syntax.basic_extended.h9"></a>
 243         <span class="phrase"><a name="boost_regex.syntax.basic_extended.single_characters"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.single_characters">Single
 244         characters:</a>
 245       </h6>
 246 <p>
 247         For example <code class="computeroutput"><span class="special">[</span><span class="identifier">abc</span><span class="special">]</span></code>, will match any of the characters 'a', 'b',
 248         or 'c'.
 249       </p>
 250 <h6>
 251 <a name="boost_regex.syntax.basic_extended.h10"></a>
 252         <span class="phrase"><a name="boost_regex.syntax.basic_extended.character_ranges"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.character_ranges">Character
 253         ranges:</a>
 254       </h6>
 255 <p>
 256         For example <code class="computeroutput"><span class="special">[</span><span class="identifier">a</span><span class="special">-</span><span class="identifier">c</span><span class="special">]</span></code>
 257         will match any single character in the range 'a' to 'c'. By default, for
 258         POSIX-Extended regular expressions, a character <span class="emphasis"><em>x</em></span> is
 259         within the range <span class="emphasis"><em>y</em></span> to <span class="emphasis"><em>z</em></span>, if it
 260         collates within that range; this results in locale specific behavior . This
 261         behavior can be turned off by unsetting the <code class="computeroutput"><span class="identifier">collate</span></code>
 262         <a class="link" href="../ref/syntax_option_type.html" title="syntax_option_type">option flag</a> - in
 263         which case whether a character appears within a range is determined by comparing
 264         the code points of the characters only.
 265       </p>
 266 <h6>
 267 <a name="boost_regex.syntax.basic_extended.h11"></a>
 268         <span class="phrase"><a name="boost_regex.syntax.basic_extended.negation"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.negation">Negation:</a>
 269       </h6>
 270 <p>
 271         If the bracket-expression begins with the ^ character, then it matches the
 272         complement of the characters it contains, for example <code class="computeroutput"><span class="special">[^</span><span class="identifier">a</span><span class="special">-</span><span class="identifier">c</span><span class="special">]</span></code> matches any character that is not in the
 273         range <code class="computeroutput"><span class="identifier">a</span><span class="special">-</span><span class="identifier">c</span></code>.
 274       </p>
 275 <h6>
 276 <a name="boost_regex.syntax.basic_extended.h12"></a>
 277         <span class="phrase"><a name="boost_regex.syntax.basic_extended.character_classes"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.character_classes">Character
 278         classes:</a>
 279       </h6>
 280 <p>
 281         An expression of the form <code class="computeroutput"><span class="special">[[:</span><span class="identifier">name</span><span class="special">:]]</span></code>
 282         matches the named character class "name", for example <code class="computeroutput"><span class="special">[[:</span><span class="identifier">lower</span><span class="special">:]]</span></code> matches any lower case character. See
 283         <a class="link" href="character_classes.html" title="Character Class Names">character class names</a>.
 284       </p>
 285 <h6>
 286 <a name="boost_regex.syntax.basic_extended.h13"></a>
 287         <span class="phrase"><a name="boost_regex.syntax.basic_extended.collating_elements"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.collating_elements">Collating
 288         Elements:</a>
 289       </h6>
 290 <p>
 291         An expression of the form <code class="computeroutput"><span class="special">[[.</span><span class="identifier">col</span><span class="special">.]</span></code> matches
 292         the collating element <span class="emphasis"><em>col</em></span>. A collating element is any
 293         single character, or any sequence of characters that collates as a single
 294         unit. Collating elements may also be used as the end point of a range, for
 295         example: <code class="computeroutput"><span class="special">[[.</span><span class="identifier">ae</span><span class="special">.]-</span><span class="identifier">c</span><span class="special">]</span></code>
 296         matches the character sequence "ae", plus any single character
 297         in the range "ae"-c, assuming that "ae" is treated as
 298         a single collating element in the current locale.
 299       </p>
 300 <p>
 301         Collating elements may be used in place of escapes (which are not normally
 302         allowed inside character sets), for example <code class="computeroutput"><span class="special">[[.^.]</span><span class="identifier">abc</span><span class="special">]</span></code> would
 303         match either one of the characters 'abc^'.
 304       </p>
 305 <p>
 306         As an extension, a collating element may also be specified via its <a class="link" href="collating_names.html" title="Collating Names">symbolic name</a>, for example:
 307       </p>
 308 <pre class="programlisting"><span class="special">[[.</span><span class="identifier">NUL</span><span class="special">.]]</span>
 309 </pre>
 310 <p>
 311         matches a NUL character.
 312       </p>
 313 <h6>
 314 <a name="boost_regex.syntax.basic_extended.h14"></a>
 315         <span class="phrase"><a name="boost_regex.syntax.basic_extended.equivalence_classes"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.equivalence_classes">Equivalence
 316         classes:</a>
 317       </h6>
 318 <p>
 319         An expression of the form <code class="computeroutput"><span class="special">[[=</span><span class="identifier">col</span><span class="special">=]]</span></code>,
 320         matches any character or collating element whose primary sort key is the
 321         same as that for collating element <span class="emphasis"><em>col</em></span>, as with collating
 322         elements the name <span class="emphasis"><em>col</em></span> may be a <a class="link" href="collating_names.html" title="Collating Names">symbolic
 323         name</a>. A primary sort key is one that ignores case, accentation, or
 324         locale-specific tailorings; so for example <code class="computeroutput"><span class="special">[[=</span><span class="identifier">a</span><span class="special">=]]</span></code> matches
 325         any of the characters: a, &#192;, &#193;, &#194;, &#195;, &#196;, &#197;, A, &#224;, &#225;, &#226;, &#227;, &#228; and &#229;. Unfortunately implementation
 326         of this is reliant on the platform's collation and localisation support;
 327         this feature can not be relied upon to work portably across all platforms,
 328         or even all locales on one platform.
 329       </p>
 330 <h6>
 331 <a name="boost_regex.syntax.basic_extended.h15"></a>
 332         <span class="phrase"><a name="boost_regex.syntax.basic_extended.combinations"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.combinations">Combinations:</a>
 333       </h6>
 334 <p>
 335         All of the above can be combined in one character set declaration, for example:
 336         <code class="computeroutput"><span class="special">[[:</span><span class="identifier">digit</span><span class="special">:]</span><span class="identifier">a</span><span class="special">-</span><span class="identifier">c</span><span class="special">[.</span><span class="identifier">NUL</span><span class="special">.]]</span></code>.
 337       </p>
 338 <h5>
 339 <a name="boost_regex.syntax.basic_extended.h16"></a>
 340         <span class="phrase"><a name="boost_regex.syntax.basic_extended.escapes"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.escapes">Escapes</a>
 341       </h5>
 342 <p>
 343         The POSIX standard defines no escape sequences for POSIX-Extended regular
 344         expressions, except that:
 345       </p>
 346 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
 347 <li class="listitem">
 348             Any special character preceded by an escape shall match itself.
 349           </li>
 350 <li class="listitem">
 351             The effect of any ordinary character being preceded by an escape is undefined.
 352           </li>
 353 <li class="listitem">
 354             An escape inside a character class declaration shall match itself: in
 355             other words the escape character is not "special" inside a
 356             character class declaration; so <code class="computeroutput"><span class="special">[\^]</span></code>
 357             will match either a literal '\' or a '^'.
 358           </li>
 359 </ul></div>
 360 <p>
 361         However, that's rather restrictive, so the following standard-compatible
 362         extensions are also supported by Boost.Regex:
 363       </p>
 364 <h6>
 365 <a name="boost_regex.syntax.basic_extended.h17"></a>
 366         <span class="phrase"><a name="boost_regex.syntax.basic_extended.escapes_matching_a_specific_char"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.escapes_matching_a_specific_char">Escapes
 367         matching a specific character</a>
 368       </h6>
 369 <p>
 370         The following escape sequences are all synonyms for single characters:
 371       </p>
 372 <div class="informaltable"><table class="table">
 373 <colgroup>
 374 <col>
 375 <col>
 376 </colgroup>
 377 <thead><tr>
 378 <th>
 379                 <p>
 380                   Escape
 381                 </p>
 382               </th>
 383 <th>
 384                 <p>
 385                   Character
 386                 </p>
 387               </th>
 388 </tr></thead>
 389 <tbody>
 390 <tr>
 391 <td>
 392                 <p>
 393                   \a
 394                 </p>
 395               </td>
 396 <td>
 397                 <p>
 398                   '\a'
 399                 </p>
 400               </td>
 401 </tr>
 402 <tr>
 403 <td>
 404                 <p>
 405                   \e
 406                 </p>
 407               </td>
 408 <td>
 409                 <p>
 410                   0x1B
 411                 </p>
 412               </td>
 413 </tr>
 414 <tr>
 415 <td>
 416                 <p>
 417                   \f
 418                 </p>
 419               </td>
 420 <td>
 421                 <p>
 422                   \f
 423                 </p>
 424               </td>
 425 </tr>
 426 <tr>
 427 <td>
 428                 <p>
 429                   \n
 430                 </p>
 431               </td>
 432 <td>
 433                 <p>
 434                   \n
 435                 </p>
 436               </td>
 437 </tr>
 438 <tr>
 439 <td>
 440                 <p>
 441                   \r
 442                 </p>
 443               </td>
 444 <td>
 445                 <p>
 446                   \r
 447                 </p>
 448               </td>
 449 </tr>
 450 <tr>
 451 <td>
 452                 <p>
 453                   \t
 454                 </p>
 455               </td>
 456 <td>
 457                 <p>
 458                   \t
 459                 </p>
 460               </td>
 461 </tr>
 462 <tr>
 463 <td>
 464                 <p>
 465                   \v
 466                 </p>
 467               </td>
 468 <td>
 469                 <p>
 470                   \v
 471                 </p>
 472               </td>
 473 </tr>
 474 <tr>
 475 <td>
 476                 <p>
 477                   \b
 478                 </p>
 479               </td>
 480 <td>
 481                 <p>
 482                   \b (but only inside a character class declaration).
 483                 </p>
 484               </td>
 485 </tr>
 486 <tr>
 487 <td>
 488                 <p>
 489                   \cX
 490                 </p>
 491               </td>
 492 <td>
 493                 <p>
 494                   An ASCII escape sequence - the character whose code point is X
 495                   % 32
 496                 </p>
 497               </td>
 498 </tr>
 499 <tr>
 500 <td>
 501                 <p>
 502                   \xdd
 503                 </p>
 504               </td>
 505 <td>
 506                 <p>
 507                   A hexadecimal escape sequence - matches the single character whose
 508                   code point is 0xdd.
 509                 </p>
 510               </td>
 511 </tr>
 512 <tr>
 513 <td>
 514                 <p>
 515                   \x{dddd}
 516                 </p>
 517               </td>
 518 <td>
 519                 <p>
 520                   A hexadecimal escape sequence - matches the single character whose
 521                   code point is 0xdddd.
 522                 </p>
 523               </td>
 524 </tr>
 525 <tr>
 526 <td>
 527                 <p>
 528                   \0ddd
 529                 </p>
 530               </td>
 531 <td>
 532                 <p>
 533                   An octal escape sequence - matches the single character whose code
 534                   point is 0ddd.
 535                 </p>
 536               </td>
 537 </tr>
 538 <tr>
 539 <td>
 540                 <p>
 541                   \N{Name}
 542                 </p>
 543               </td>
 544 <td>
 545                 <p>
 546                   Matches the single character which has the symbolic name <span class="emphasis"><em>Name</em></span>.
 547                   For example <code class="computeroutput"><span class="special">\\</span><span class="identifier">N</span><span class="special">{</span><span class="identifier">newline</span><span class="special">}</span></code> matches the single character \n.
 548                 </p>
 549               </td>
 550 </tr>
 551 </tbody>
 552 </table></div>
 553 <h6>
 554 <a name="boost_regex.syntax.basic_extended.h18"></a>
 555         <span class="phrase"><a name="boost_regex.syntax.basic_extended.single_character_character_class"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.single_character_character_class">"Single
 556         character" character classes:</a>
 557       </h6>
 558 <p>
 559         Any escaped character <span class="emphasis"><em>x</em></span>, if <span class="emphasis"><em>x</em></span> is
 560         the name of a character class shall match any character that is a member
 561         of that class, and any escaped character <span class="emphasis"><em>X</em></span>, if <span class="emphasis"><em>x</em></span>
 562         is the name of a character class, shall match any character not in that class.
 563       </p>
 564 <p>
 565         The following are supported by default:
 566       </p>
 567 <div class="informaltable"><table class="table">
 568 <colgroup>
 569 <col>
 570 <col>
 571 </colgroup>
 572 <thead><tr>
 573 <th>
 574                 <p>
 575                   Escape sequence
 576                 </p>
 577               </th>
 578 <th>
 579                 <p>
 580                   Equivalent to
 581                 </p>
 582               </th>
 583 </tr></thead>
 584 <tbody>
 585 <tr>
 586 <td>
 587                 <p>
 588                   <code class="computeroutput"><span class="special">\</span><span class="identifier">d</span></code>
 589                 </p>
 590               </td>
 591 <td>
 592                 <p>
 593                   <code class="computeroutput"><span class="special">[[:</span><span class="identifier">digit</span><span class="special">:]]</span></code>
 594                 </p>
 595               </td>
 596 </tr>
 597 <tr>
 598 <td>
 599                 <p>
 600                   <code class="computeroutput"><span class="special">\</span><span class="identifier">l</span></code>
 601                 </p>
 602               </td>
 603 <td>
 604                 <p>
 605                   <code class="computeroutput"><span class="special">[[:</span><span class="identifier">lower</span><span class="special">:]]</span></code>
 606                 </p>
 607               </td>
 608 </tr>
 609 <tr>
 610 <td>
 611                 <p>
 612                   <code class="computeroutput"><span class="special">\</span><span class="identifier">s</span></code>
 613                 </p>
 614               </td>
 615 <td>
 616                 <p>
 617                   <code class="computeroutput"><span class="special">[[:</span><span class="identifier">space</span><span class="special">:]]</span></code>
 618                 </p>
 619               </td>
 620 </tr>
 621 <tr>
 622 <td>
 623                 <p>
 624                   <code class="computeroutput"><span class="special">\</span><span class="identifier">u</span></code>
 625                 </p>
 626               </td>
 627 <td>
 628                 <p>
 629                   <code class="computeroutput"><span class="special">[[:</span><span class="identifier">upper</span><span class="special">:]]</span></code>
 630                 </p>
 631               </td>
 632 </tr>
 633 <tr>
 634 <td>
 635                 <p>
 636                   <code class="computeroutput"><span class="special">\</span><span class="identifier">w</span></code>
 637                 </p>
 638               </td>
 639 <td>
 640                 <p>
 641                   <code class="computeroutput"><span class="special">[[:</span><span class="identifier">word</span><span class="special">:]]</span></code>
 642                 </p>
 643               </td>
 644 </tr>
 645 <tr>
 646 <td>
 647                 <p>
 648                   <code class="computeroutput"><span class="special">\</span><span class="identifier">D</span></code>
 649                 </p>
 650               </td>
 651 <td>
 652                 <p>
 653                   <code class="computeroutput"><span class="special">[^[:</span><span class="identifier">digit</span><span class="special">:]]</span></code>
 654                 </p>
 655               </td>
 656 </tr>
 657 <tr>
 658 <td>
 659                 <p>
 660                   <code class="computeroutput"><span class="special">\</span><span class="identifier">L</span></code>
 661                 </p>
 662               </td>
 663 <td>
 664                 <p>
 665                   <code class="computeroutput"><span class="special">[^[:</span><span class="identifier">lower</span><span class="special">:]]</span></code>
 666                 </p>
 667               </td>
 668 </tr>
 669 <tr>
 670 <td>
 671                 <p>
 672                   <code class="computeroutput"><span class="special">\</span><span class="identifier">S</span></code>
 673                 </p>
 674               </td>
 675 <td>
 676                 <p>
 677                   <code class="computeroutput"><span class="special">[^[:</span><span class="identifier">space</span><span class="special">:]]</span></code>
 678                 </p>
 679               </td>
 680 </tr>
 681 <tr>
 682 <td>
 683                 <p>
 684                   <code class="computeroutput"><span class="special">\</span><span class="identifier">U</span></code>
 685                 </p>
 686               </td>
 687 <td>
 688                 <p>
 689                   <code class="computeroutput"><span class="special">[^[:</span><span class="identifier">upper</span><span class="special">:]]</span></code>
 690                 </p>
 691               </td>
 692 </tr>
 693 <tr>
 694 <td>
 695                 <p>
 696                   <code class="computeroutput"><span class="special">\</span><span class="identifier">W</span></code>
 697                 </p>
 698               </td>
 699 <td>
 700                 <p>
 701                   <code class="computeroutput"><span class="special">[^[:</span><span class="identifier">word</span><span class="special">:]]</span></code>
 702                 </p>
 703               </td>
 704 </tr>
 705 </tbody>
 706 </table></div>
 707 <h6>
 708 <a name="boost_regex.syntax.basic_extended.h19"></a>
 709         <span class="phrase"><a name="boost_regex.syntax.basic_extended.character_properties"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.character_properties">Character
 710         Properties</a>
 711       </h6>
 712 <p>
 713         The character property names in the following table are all equivalent to
 714         the names used in character classes.
 715       </p>
 716 <div class="informaltable"><table class="table">
 717 <colgroup>
 718 <col>
 719 <col>
 720 <col>
 721 </colgroup>
 722 <thead><tr>
 723 <th>
 724                 <p>
 725                   Form
 726                 </p>
 727               </th>
 728 <th>
 729                 <p>
 730                   Description
 731                 </p>
 732               </th>
 733 <th>
 734                 <p>
 735                   Equivalent character set form
 736                 </p>
 737               </th>
 738 </tr></thead>
 739 <tbody>
 740 <tr>
 741 <td>
 742                 <p>
 743                   <code class="computeroutput"><span class="special">\</span><span class="identifier">pX</span></code>
 744                 </p>
 745               </td>
 746 <td>
 747                 <p>
 748                   Matches any character that has the property X.
 749                 </p>
 750               </td>
 751 <td>
 752                 <p>
 753                   <code class="computeroutput"><span class="special">[[:</span><span class="identifier">X</span><span class="special">:]]</span></code>
 754                 </p>
 755               </td>
 756 </tr>
 757 <tr>
 758 <td>
 759                 <p>
 760                   <code class="computeroutput"><span class="special">\</span><span class="identifier">p</span><span class="special">{</span><span class="identifier">Name</span><span class="special">}</span></code>
 761                 </p>
 762               </td>
 763 <td>
 764                 <p>
 765                   Matches any character that has the property Name.
 766                 </p>
 767               </td>
 768 <td>
 769                 <p>
 770                   <code class="computeroutput"><span class="special">[[:</span><span class="identifier">Name</span><span class="special">:]]</span></code>
 771                 </p>
 772               </td>
 773 </tr>
 774 <tr>
 775 <td>
 776                 <p>
 777                   <code class="computeroutput"><span class="special">\</span><span class="identifier">PX</span></code>
 778                 </p>
 779               </td>
 780 <td>
 781                 <p>
 782                   Matches any character that does not have the property X.
 783                 </p>
 784               </td>
 785 <td>
 786                 <p>
 787                   <code class="computeroutput"><span class="special">[^[:</span><span class="identifier">X</span><span class="special">:]]</span></code>
 788                 </p>
 789               </td>
 790 </tr>
 791 <tr>
 792 <td>
 793                 <p>
 794                   <code class="computeroutput"><span class="special">\</span><span class="identifier">P</span><span class="special">{</span><span class="identifier">Name</span><span class="special">}</span></code>
 795                 </p>
 796               </td>
 797 <td>
 798                 <p>
 799                   Matches any character that does not have the property Name.
 800                 </p>
 801               </td>
 802 <td>
 803                 <p>
 804                   <code class="computeroutput"><span class="special">[^[:</span><span class="identifier">Name</span><span class="special">:]]</span></code>
 805                 </p>
 806               </td>
 807 </tr>
 808 </tbody>
 809 </table></div>
 810 <p>
 811         For example <code class="computeroutput"><span class="special">\</span><span class="identifier">pd</span></code>
 812         matches any "digit" character, as does <code class="computeroutput"><span class="special">\</span><span class="identifier">p</span><span class="special">{</span><span class="identifier">digit</span><span class="special">}</span></code>.
 813       </p>
 814 <h6>
 815 <a name="boost_regex.syntax.basic_extended.h20"></a>
 816         <span class="phrase"><a name="boost_regex.syntax.basic_extended.word_boundaries"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.word_boundaries">Word
 817         Boundaries</a>
 818       </h6>
 819 <p>
 820         The following escape sequences match the boundaries of words:
 821       </p>
 822 <div class="informaltable"><table class="table">
 823 <colgroup>
 824 <col>
 825 <col>
 826 </colgroup>
 827 <thead><tr>
 828 <th>
 829                 <p>
 830                   Escape
 831                 </p>
 832               </th>
 833 <th>
 834                 <p>
 835                   Meaning
 836                 </p>
 837               </th>
 838 </tr></thead>
 839 <tbody>
 840 <tr>
 841 <td>
 842                 <p>
 843                   <code class="computeroutput"><span class="special">\&lt;</span></code>
 844                 </p>
 845               </td>
 846 <td>
 847                 <p>
 848                   Matches the start of a word.
 849                 </p>
 850               </td>
 851 </tr>
 852 <tr>
 853 <td>
 854                 <p>
 855                   <code class="computeroutput"><span class="special">\&gt;</span></code>
 856                 </p>
 857               </td>
 858 <td>
 859                 <p>
 860                   Matches the end of a word.
 861                 </p>
 862               </td>
 863 </tr>
 864 <tr>
 865 <td>
 866                 <p>
 867                   <code class="computeroutput"><span class="special">\</span><span class="identifier">b</span></code>
 868                 </p>
 869               </td>
 870 <td>
 871                 <p>
 872                   Matches a word boundary (the start or end of a word).
 873                 </p>
 874               </td>
 875 </tr>
 876 <tr>
 877 <td>
 878                 <p>
 879                   <code class="computeroutput"><span class="special">\</span><span class="identifier">B</span></code>
 880                 </p>
 881               </td>
 882 <td>
 883                 <p>
 884                   Matches only when not at a word boundary.
 885                 </p>
 886               </td>
 887 </tr>
 888 </tbody>
 889 </table></div>
 890 <h6>
 891 <a name="boost_regex.syntax.basic_extended.h21"></a>
 892         <span class="phrase"><a name="boost_regex.syntax.basic_extended.buffer_boundaries"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.buffer_boundaries">Buffer
 893         boundaries</a>
 894       </h6>
 895 <p>
 896         The following match only at buffer boundaries: a "buffer" in this
 897         context is the whole of the input text that is being matched against (note
 898         that ^ and $ may match embedded newlines within the text).
 899       </p>
 900 <div class="informaltable"><table class="table">
 901 <colgroup>
 902 <col>
 903 <col>
 904 </colgroup>
 905 <thead><tr>
 906 <th>
 907                 <p>
 908                   Escape
 909                 </p>
 910               </th>
 911 <th>
 912                 <p>
 913                   Meaning
 914                 </p>
 915               </th>
 916 </tr></thead>
 917 <tbody>
 918 <tr>
 919 <td>
 920                 <p>
 921                   \`
 922                 </p>
 923               </td>
 924 <td>
 925                 <p>
 926                   Matches at the start of a buffer only.
 927                 </p>
 928               </td>
 929 </tr>
 930 <tr>
 931 <td>
 932                 <p>
 933                   \'
 934                 </p>
 935               </td>
 936 <td>
 937                 <p>
 938                   Matches at the end of a buffer only.
 939                 </p>
 940               </td>
 941 </tr>
 942 <tr>
 943 <td>
 944                 <p>
 945                   <code class="computeroutput"><span class="special">\</span><span class="identifier">A</span></code>
 946                 </p>
 947               </td>
 948 <td>
 949                 <p>
 950                   Matches at the start of a buffer only (the same as \`).
 951                 </p>
 952               </td>
 953 </tr>
 954 <tr>
 955 <td>
 956                 <p>
 957                   <code class="computeroutput"><span class="special">\</span><span class="identifier">z</span></code>
 958                 </p>
 959               </td>
 960 <td>
 961                 <p>
 962                   Matches at the end of a buffer only (the same as \').
 963                 </p>
 964               </td>
 965 </tr>
 966 <tr>
 967 <td>
 968                 <p>
 969                   <code class="computeroutput"><span class="special">\</span><span class="identifier">Z</span></code>
 970                 </p>
 971               </td>
 972 <td>
 973                 <p>
 974                   Matches an optional sequence of newlines at the end of a buffer:
 975                   equivalent to the regular expression <code class="computeroutput"><span class="special">\</span><span class="identifier">n</span><span class="special">*\</span><span class="identifier">z</span></code>
 976                 </p>
 977               </td>
 978 </tr>
 979 </tbody>
 980 </table></div>
 981 <h6>
 982 <a name="boost_regex.syntax.basic_extended.h22"></a>
 983         <span class="phrase"><a name="boost_regex.syntax.basic_extended.continuation_escape"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.continuation_escape">Continuation
 984         Escape</a>
 985       </h6>
 986 <p>
 987         The sequence <code class="computeroutput"><span class="special">\</span><span class="identifier">G</span></code>
 988         matches only at the end of the last match found, or at the start of the text
 989         being matched if no previous match was found. This escape useful if you're
 990         iterating over the matches contained within a text, and you want each subsequence
 991         match to start where the last one ended.
 992       </p>
 993 <h6>
 994 <a name="boost_regex.syntax.basic_extended.h23"></a>
 995         <span class="phrase"><a name="boost_regex.syntax.basic_extended.quoting_escape"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.quoting_escape">Quoting
 996         escape</a>
 997       </h6>
 998 <p>
 999         The escape sequence <code class="computeroutput"><span class="special">\</span><span class="identifier">Q</span></code>
1000         begins a "quoted sequence": all the subsequent characters are treated
1001         as literals, until either the end of the regular expression or <code class="computeroutput"><span class="special">\</span><span class="identifier">E</span></code> is found.
1002         For example the expression: <code class="computeroutput"><span class="special">\</span><span class="identifier">Q</span><span class="special">\*+\</span><span class="identifier">Ea</span><span class="special">+</span></code> would match either of:
1003       </p>
1004 <pre class="programlisting"><span class="special">\*+</span><span class="identifier">a</span>
1005 <span class="special">\*+</span><span class="identifier">aaa</span>
1006 </pre>
1007 <h6>
1008 <a name="boost_regex.syntax.basic_extended.h24"></a>
1009         <span class="phrase"><a name="boost_regex.syntax.basic_extended.unicode_escapes"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.unicode_escapes">Unicode
1010         escapes</a>
1011       </h6>
1012 <div class="informaltable"><table class="table">
1013 <colgroup>
1014 <col>
1015 <col>
1016 </colgroup>
1017 <thead><tr>
1018 <th>
1019                 <p>
1020                   Escape
1021                 </p>
1022               </th>
1023 <th>
1024                 <p>
1025                   Meaning
1026                 </p>
1027               </th>
1028 </tr></thead>
1029 <tbody>
1030 <tr>
1031 <td>
1032                 <p>
1033                   <code class="computeroutput"><span class="special">\</span><span class="identifier">C</span></code>
1034                 </p>
1035               </td>
1036 <td>
1037                 <p>
1038                   Matches a single code point: in Boost regex this has exactly the
1039                   same effect as a "." operator.
1040                 </p>
1041               </td>
1042 </tr>
1043 <tr>
1044 <td>
1045                 <p>
1046                   <code class="computeroutput"><span class="special">\</span><span class="identifier">X</span></code>
1047                 </p>
1048               </td>
1049 <td>
1050                 <p>
1051                   Matches a combining character sequence: that is any non-combining
1052                   character followed by a sequence of zero or more combining characters.
1053                 </p>
1054               </td>
1055 </tr>
1056 </tbody>
1057 </table></div>
1058 <h6>
1059 <a name="boost_regex.syntax.basic_extended.h25"></a>
1060         <span class="phrase"><a name="boost_regex.syntax.basic_extended.any_other_escape"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.any_other_escape">Any
1061         other escape</a>
1062       </h6>
1063 <p>
1064         Any other escape sequence matches the character that is escaped, for example
1065         \@ matches a literal '@'.
1066       </p>
1067 <h5>
1068 <a name="boost_regex.syntax.basic_extended.h26"></a>
1069         <span class="phrase"><a name="boost_regex.syntax.basic_extended.operator_precedence"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.operator_precedence">Operator
1070         precedence</a>
1071       </h5>
1072 <p>
1073         The order of precedence for of operators is as follows:
1074       </p>
1075 <div class="orderedlist"><ol class="orderedlist" type="1">
1076 <li class="listitem">
1077             Collation-related bracket symbols <code class="computeroutput"><span class="special">[==]</span>
1078             <span class="special">[::]</span> <span class="special">[..]</span></code>
1079           </li>
1080 <li class="listitem">
1081             Escaped characters <code class="computeroutput"><span class="special">\</span></code>
1082           </li>
1083 <li class="listitem">
1084             Character set (bracket expression) <code class="computeroutput"><span class="special">[]</span></code>
1085           </li>
1086 <li class="listitem">
1087             Grouping <code class="computeroutput"><span class="special">()</span></code>
1088           </li>
1089 <li class="listitem">
1090             Single-character-ERE duplication <code class="computeroutput"><span class="special">*</span>
1091             <span class="special">+</span> <span class="special">?</span>
1092             <span class="special">{</span><span class="identifier">m</span><span class="special">,</span><span class="identifier">n</span><span class="special">}</span></code>
1093           </li>
1094 <li class="listitem">
1095             Concatenation
1096           </li>
1097 <li class="listitem">
1098             Anchoring ^$
1099           </li>
1100 <li class="listitem">
1101             Alternation <code class="computeroutput"><span class="special">|</span></code>
1102           </li>
1103 </ol></div>
1104 <h5>
1105 <a name="boost_regex.syntax.basic_extended.h27"></a>
1106         <span class="phrase"><a name="boost_regex.syntax.basic_extended.what_gets_matched"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.what_gets_matched">What
1107         Gets Matched</a>
1108       </h5>
1109 <p>
1110         When there is more that one way to match a regular expression, the "best"
1111         possible match is obtained using the <a class="link" href="leftmost_longest_rule.html" title="The Leftmost Longest Rule">leftmost-longest
1112         rule</a>.
1113       </p>
1114 <h4>
1115 <a name="boost_regex.syntax.basic_extended.h28"></a>
1116         <span class="phrase"><a name="boost_regex.syntax.basic_extended.variations"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.variations">Variations</a>
1117       </h4>
1118 <h5>
1119 <a name="boost_regex.syntax.basic_extended.h29"></a>
1120         <span class="phrase"><a name="boost_regex.syntax.basic_extended.egrep"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.egrep">Egrep</a>
1121       </h5>
1122 <p>
1123         When an expression is compiled with the <a class="link" href="../ref/syntax_option_type.html" title="syntax_option_type">flag
1124         <code class="computeroutput"><span class="identifier">egrep</span></code></a> set, then the
1125         expression is treated as a newline separated list of <a class="link" href="basic_extended.html#boost_regex.posix_extended_syntax">POSIX-Extended
1126         expressions</a>, a match is found if any of the expressions in the list
1127         match, for example:
1128       </p>
1129 <pre class="programlisting"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">regex</span> <span class="identifier">e</span><span class="special">(</span><span class="string">"abc\ndef"</span><span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">regex</span><span class="special">::</span><span class="identifier">egrep</span><span class="special">);</span>
1130 </pre>
1131 <p>
1132         will match either of the POSIX-Basic expressions "abc" or "def".
1133       </p>
1134 <p>
1135         As its name suggests, this behavior is consistent with the Unix utility
1136         <code class="computeroutput"><span class="identifier">egrep</span></code>, and with grep when
1137         used with the -E option.
1138       </p>
1139 <h5>
1140 <a name="boost_regex.syntax.basic_extended.h30"></a>
1141         <span class="phrase"><a name="boost_regex.syntax.basic_extended.awk"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.awk">awk</a>
1142       </h5>
1143 <p>
1144         In addition to the <a class="link" href="basic_extended.html#boost_regex.posix_extended_syntax">POSIX-Extended
1145         features</a> the escape character is special inside a character class
1146         declaration.
1147       </p>
1148 <p>
1149         In addition, some escape sequences that are not defined as part of POSIX-Extended
1150         specification are required to be supported - however Boost.Regex supports
1151         these by default anyway.
1152       </p>
1153 <h4>
1154 <a name="boost_regex.syntax.basic_extended.h31"></a>
1155         <span class="phrase"><a name="boost_regex.syntax.basic_extended.options"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.options">Options</a>
1156       </h4>
1157 <p>
1158         There are a <a class="link" href="../ref/syntax_option_type/syntax_option_type_extended.html" title="Options for POSIX Extended Regular Expressions">variety
1159         of flags</a> that may be combined with the <code class="computeroutput"><span class="identifier">extended</span></code>
1160         and <code class="computeroutput"><span class="identifier">egrep</span></code> options when constructing
1161         the regular expression, in particular note that the <a class="link" href="../ref/syntax_option_type/syntax_option_type_extended.html" title="Options for POSIX Extended Regular Expressions"><code class="computeroutput"><span class="identifier">newline_alt</span></code></a> option alters the syntax,
1162         while the <a class="link" href="../ref/syntax_option_type/syntax_option_type_extended.html" title="Options for POSIX Extended Regular Expressions"><code class="computeroutput"><span class="identifier">collate</span></code>, <code class="computeroutput"><span class="identifier">nosubs</span></code>
1163         and <code class="computeroutput"><span class="identifier">icase</span></code> options</a>
1164         modify how the case and locale sensitivity are to be applied.
1165       </p>
1166 <h4>
1167 <a name="boost_regex.syntax.basic_extended.h32"></a>
1168         <span class="phrase"><a name="boost_regex.syntax.basic_extended.references"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.references">References</a>
1169       </h4>
1170 <p>
1171         <a href="http://www.opengroup.org/onlinepubs/000095399/basedefs/xbd_chap09.html" target="_top">IEEE
1172         Std 1003.1-2001, Portable Operating System Interface (POSIX ), Base Definitions
1173         and Headers, Section 9, Regular Expressions.</a>
1174       </p>
1175 <p>
1176         <a href="http://www.opengroup.org/onlinepubs/000095399/utilities/grep.html" target="_top">IEEE
1177         Std 1003.1-2001, Portable Operating System Interface (POSIX ), Shells and
1178         Utilities, Section 4, Utilities, egrep.</a>
1179       </p>
1180 <p>
1181         <a href="http://www.opengroup.org/onlinepubs/000095399/utilities/awk.html" target="_top">IEEE
1182         Std 1003.1-2001, Portable Operating System Interface (POSIX ), Shells and
1183         Utilities, Section 4, Utilities, awk.</a>
1184       </p>
1185 </div>
1186 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
1187 <td align="left"></td>
1188 <td align="right"><div class="copyright-footer">Copyright &#169; 1998-2013 John Maddock<p>
1189         Distributed under the Boost Software License, Version 1.0. (See accompanying
1190         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>)
1191       </p>
1192 </div></td>
1193 </tr></table>
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