1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Localization</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="Boost.Regex 5.1.4"> 8<link rel="up" href="../background.html" title="Background Information"> 9<link rel="prev" href="headers.html" title="Headers"> 10<link rel="next" href="thread_safety.html" title="Thread Safety"> 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="headers.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../background.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="thread_safety.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h3 class="title"> 27<a name="boost_regex.background.locale"></a><a class="link" href="locale.html" title="Localization">Localization</a> 28</h3></div></div></div> 29<p> 30 Boost.Regex provides extensive support for run-time localization, the localization 31 model used can be split into two parts: front-end and back-end. 32 </p> 33<p> 34 Front-end localization deals with everything which the user sees - error 35 messages, and the regular expression syntax itself. For example a French 36 application could change [[:word:]] to [[:mot:]] and \w to \m. Modifying 37 the front end locale requires active support from the developer, by providing 38 the library with a message catalogue to load, containing the localized strings. 39 Front-end locale is affected by the LC_MESSAGES category only. 40 </p> 41<p> 42 Back-end localization deals with everything that occurs after the expression 43 has been parsed - in other words everything that the user does not see or 44 interact with directly. It deals with case conversion, collation, and character 45 class membership. The back-end locale does not require any intervention from 46 the developer - the library will acquire all the information it requires 47 for the current locale from the underlying operating system / run time library. 48 This means that if the program user does not interact with regular expressions 49 directly - for example if the expressions are embedded in your C++ code - 50 then no explicit localization is required, as the library will take care 51 of everything for you. For example embedding the expression [[:word:]]+ in 52 your code will always match a whole word, if the program is run on a machine 53 with, for example, a Greek locale, then it will still match a whole word, 54 but in Greek characters rather than Latin ones. The back-end locale is affected 55 by the LC_TYPE and LC_COLLATE categories. 56 </p> 57<p> 58 There are three separate localization mechanisms supported by Boost.Regex: 59 </p> 60<h5> 61<a name="boost_regex.background.locale.h0"></a> 62 <span class="phrase"><a name="boost_regex.background.locale.win32_localization_model"></a></span><a class="link" href="locale.html#boost_regex.background.locale.win32_localization_model">Win32 localization 63 model.</a> 64 </h5> 65<p> 66 This is the default model when the library is compiled under Win32, and is 67 encapsulated by the traits class <code class="computeroutput"><span class="identifier">w32_regex_traits</span></code>. 68 When this model is in effect each <a class="link" href="../ref/basic_regex.html" title="basic_regex"><code class="computeroutput"><span class="identifier">basic_regex</span></code></a> object gets it's own 69 LCID, by default this is the users default setting as returned by GetUserDefaultLCID, 70 but you can call imbue on the <code class="computeroutput"><span class="identifier">basic_regex</span></code> 71 object to set it's locale to some other LCID if you wish. All the settings 72 used by Boost.Regex are acquired directly from the operating system bypassing 73 the C run time library. Front-end localization requires a resource dll, containing 74 a string table with the user-defined strings. The traits class exports the 75 function: 76 </p> 77<pre class="programlisting"><span class="keyword">static</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">set_message_catalogue</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&</span> <span class="identifier">s</span><span class="special">);</span> 78</pre> 79<p> 80 which needs to be called with a string identifying the name of the resource 81 dll, before your code compiles any regular expressions (but not necessarily 82 before you construct any <code class="computeroutput"><span class="identifier">basic_regex</span></code> 83 instances): 84 </p> 85<pre class="programlisting"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">w32_regex_traits</span><span class="special"><</span><span class="keyword">char</span><span class="special">>::</span><span class="identifier">set_message_catalogue</span><span class="special">(</span><span class="string">"mydll.dll"</span><span class="special">);</span> 86</pre> 87<p> 88 The library provides full Unicode support under NT, under Windows 9x the 89 library degrades gracefully - characters 0 to 255 are supported, the remainder 90 are treated as "unknown" graphic characters. 91 </p> 92<h5> 93<a name="boost_regex.background.locale.h1"></a> 94 <span class="phrase"><a name="boost_regex.background.locale.c_localization_model"></a></span><a class="link" href="locale.html#boost_regex.background.locale.c_localization_model">C 95 localization model.</a> 96 </h5> 97<p> 98 This model has been deprecated in favor of the C++ locale for all non-Windows 99 compilers that support it. This locale is encapsulated by the traits class 100 <code class="computeroutput"><span class="identifier">c_regex_traits</span></code>, Win32 users 101 can force this model to take effect by defining the pre-processor symbol 102 BOOST_REGEX_USE_C_LOCALE. When this model is in effect there is a single 103 global locale, as set by <code class="computeroutput"><span class="identifier">setlocale</span></code>. 104 All settings are acquired from your run time library, consequently Unicode 105 support is dependent upon your run time library implementation. 106 </p> 107<p> 108 Front end localization is not supported. 109 </p> 110<p> 111 Note that calling setlocale invalidates all compiled regular expressions, 112 calling <code class="computeroutput"><span class="identifier">setlocale</span><span class="special">(</span><span class="identifier">LC_ALL</span><span class="special">,</span> <span class="string">"C"</span><span class="special">)</span></code> 113 will make this library behave equivalent to most traditional regular expression 114 libraries including version 1 of this library. 115 </p> 116<h5> 117<a name="boost_regex.background.locale.h2"></a> 118 <span class="phrase"><a name="boost_regex.background.locale.c_localization_model0"></a></span><a class="link" href="locale.html#boost_regex.background.locale.c_localization_model0">C++ 119 localization model.</a> 120 </h5> 121<p> 122 This model is the default for non-Windows compilers. 123 </p> 124<p> 125 When this model is in effect each instance of <a class="link" href="../ref/basic_regex.html" title="basic_regex"><code class="computeroutput"><span class="identifier">basic_regex</span></code></a> has its own instance 126 of <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">locale</span></code>, class <a class="link" href="../ref/basic_regex.html" title="basic_regex"><code class="computeroutput"><span class="identifier">basic_regex</span></code></a> also has a member function 127 <code class="computeroutput"><span class="identifier">imbue</span></code> which allows the locale 128 for the expression to be set on a per-instance basis. Front end localization 129 requires a POSIX message catalogue, which will be loaded via the <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">messages</span></code> 130 facet of the expression's locale, the traits class exports the symbol: 131 </p> 132<pre class="programlisting"><span class="keyword">static</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">set_message_catalogue</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&</span> <span class="identifier">s</span><span class="special">);</span> 133</pre> 134<p> 135 which needs to be called with a string identifying the name of the message 136 catalogue, before your code compiles any regular expressions (but not necessarily 137 before you construct any basic_regex instances): 138 </p> 139<pre class="programlisting"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">cpp_regex_traits</span><span class="special"><</span><span class="keyword">char</span><span class="special">>::</span><span class="identifier">set_message_catalogue</span><span class="special">(</span><span class="string">"mycatalogue"</span><span class="special">);</span> 140</pre> 141<p> 142 Note that calling <code class="computeroutput"><span class="identifier">basic_regex</span><span class="special"><>::</span><span class="identifier">imbue</span></code> 143 will invalidate any expression currently compiled in that instance of <a class="link" href="../ref/basic_regex.html" title="basic_regex"><code class="computeroutput"><span class="identifier">basic_regex</span></code></a>. 144 </p> 145<p> 146 Finally note that if you build the library with a non-default localization 147 model, then the appropriate pre-processor symbol (BOOST_REGEX_USE_C_LOCALE 148 or BOOST_REGEX_USE_CPP_LOCALE) must be defined both when you build the support 149 library, and when you include <code class="computeroutput"><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">hpp</span><span class="special">></span></code> 150 or <code class="computeroutput"><span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">cregex</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span></code> 151 in your code. The best way to ensure this is to add the #define to <code class="computeroutput"><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">user</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span></code>. 152 </p> 153<h5> 154<a name="boost_regex.background.locale.h3"></a> 155 <span class="phrase"><a name="boost_regex.background.locale.providing_a_message_catalogue"></a></span><a class="link" href="locale.html#boost_regex.background.locale.providing_a_message_catalogue">Providing 156 a message catalogue</a> 157 </h5> 158<p> 159 In order to localize the front end of the library, you need to provide the 160 library with the appropriate message strings contained either in a resource 161 dll's string table (Win32 model), or a POSIX message catalogue (C++ models). 162 In the latter case the messages must appear in message set zero of the catalogue. 163 The messages and their id's are as follows: 164 </p> 165<div class="informaltable"><table class="table"> 166<colgroup> 167<col> 168<col> 169<col> 170</colgroup> 171<thead><tr> 172<th> 173 <p> 174 Message 175 </p> 176 </th> 177<th> 178 <p> 179 id 180 </p> 181 </th> 182<th> 183 <p> 184 Meaning 185 </p> 186 </th> 187<th> 188 <p> 189 Default value 190 </p> 191 </th> 192</tr></thead> 193<tbody> 194<tr> 195<td> 196 <p> 197 101 198 </p> 199 </td> 200<td> 201 <p> 202 The character used to start a sub-expression. 203 </p> 204 </td> 205<td> 206 <p> 207 "(" 208 </p> 209 </td> 210</tr> 211<tr> 212<td> 213 <p> 214 102 215 </p> 216 </td> 217<td> 218 <p> 219 The character used to end a sub-expression declaration. 220 </p> 221 </td> 222<td> 223 <p> 224 ")" 225 </p> 226 </td> 227</tr> 228<tr> 229<td> 230 <p> 231 103 232 </p> 233 </td> 234<td> 235 <p> 236 The character used to denote an end of line assertion. 237 </p> 238 </td> 239<td> 240 <p> 241 "$" 242 </p> 243 </td> 244</tr> 245<tr> 246<td> 247 <p> 248 104 249 </p> 250 </td> 251<td> 252 <p> 253 The character used to denote the start of line assertion. 254 </p> 255 </td> 256<td> 257 <p> 258 "^" 259 </p> 260 </td> 261</tr> 262<tr> 263<td> 264 <p> 265 105 266 </p> 267 </td> 268<td> 269 <p> 270 The character used to denote the "match any character expression". 271 </p> 272 </td> 273<td> 274 <p> 275 "." 276 </p> 277 </td> 278</tr> 279<tr> 280<td> 281 <p> 282 106 283 </p> 284 </td> 285<td> 286 <p> 287 The match zero or more times repetition operator. 288 </p> 289 </td> 290<td> 291 <p> 292 "*" 293 </p> 294 </td> 295</tr> 296<tr> 297<td> 298 <p> 299 107 300 </p> 301 </td> 302<td> 303 <p> 304 The match one or more repetition operator. 305 </p> 306 </td> 307<td> 308 <p> 309 "+" 310 </p> 311 </td> 312</tr> 313<tr> 314<td> 315 <p> 316 108 317 </p> 318 </td> 319<td> 320 <p> 321 The match zero or one repetition operator. 322 </p> 323 </td> 324<td> 325 <p> 326 "?" 327 </p> 328 </td> 329</tr> 330<tr> 331<td> 332 <p> 333 109 334 </p> 335 </td> 336<td> 337 <p> 338 The character set opening character. 339 </p> 340 </td> 341<td> 342 <p> 343 "[" 344 </p> 345 </td> 346</tr> 347<tr> 348<td> 349 <p> 350 110 351 </p> 352 </td> 353<td> 354 <p> 355 The character set closing character. 356 </p> 357 </td> 358<td> 359 <p> 360 "]" 361 </p> 362 </td> 363</tr> 364<tr> 365<td> 366 <p> 367 111 368 </p> 369 </td> 370<td> 371 <p> 372 The alternation operator. 373 </p> 374 </td> 375<td> 376 <p> 377 "|" 378 </p> 379 </td> 380</tr> 381<tr> 382<td> 383 <p> 384 112 385 </p> 386 </td> 387<td> 388 <p> 389 The escape character. 390 </p> 391 </td> 392<td> 393 <p> 394 "\" 395 </p> 396 </td> 397</tr> 398<tr> 399<td> 400 <p> 401 113 402 </p> 403 </td> 404<td> 405 <p> 406 The hash character (not currently used). 407 </p> 408 </td> 409<td> 410 <p> 411 "#" 412 </p> 413 </td> 414</tr> 415<tr> 416<td> 417 <p> 418 114 419 </p> 420 </td> 421<td> 422 <p> 423 The range operator. 424 </p> 425 </td> 426<td> 427 <p> 428 "-" 429 </p> 430 </td> 431</tr> 432<tr> 433<td> 434 <p> 435 115 436 </p> 437 </td> 438<td> 439 <p> 440 The repetition operator opening character. 441 </p> 442 </td> 443<td> 444 <p> 445 "{" 446 </p> 447 </td> 448</tr> 449<tr> 450<td> 451 <p> 452 116 453 </p> 454 </td> 455<td> 456 <p> 457 The repetition operator closing character. 458 </p> 459 </td> 460<td> 461 <p> 462 "}" 463 </p> 464 </td> 465</tr> 466<tr> 467<td> 468 <p> 469 117 470 </p> 471 </td> 472<td> 473 <p> 474 The digit characters. 475 </p> 476 </td> 477<td> 478 <p> 479 "0123456789" 480 </p> 481 </td> 482</tr> 483<tr> 484<td> 485 <p> 486 118 487 </p> 488 </td> 489<td> 490 <p> 491 The character which when preceded by an escape character represents 492 the word boundary assertion. 493 </p> 494 </td> 495<td> 496 <p> 497 "b" 498 </p> 499 </td> 500</tr> 501<tr> 502<td> 503 <p> 504 119 505 </p> 506 </td> 507<td> 508 <p> 509 The character which when preceded by an escape character represents 510 the non-word boundary assertion. 511 </p> 512 </td> 513<td> 514 <p> 515 "B" 516 </p> 517 </td> 518</tr> 519<tr> 520<td> 521 <p> 522 120 523 </p> 524 </td> 525<td> 526 <p> 527 The character which when preceded by an escape character represents 528 the word-start boundary assertion. 529 </p> 530 </td> 531<td> 532 <p> 533 "<" 534 </p> 535 </td> 536</tr> 537<tr> 538<td> 539 <p> 540 121 541 </p> 542 </td> 543<td> 544 <p> 545 The character which when preceded by an escape character represents 546 the word-end boundary assertion. 547 </p> 548 </td> 549<td> 550 <p> 551 ">" 552 </p> 553 </td> 554</tr> 555<tr> 556<td> 557 <p> 558 122 559 </p> 560 </td> 561<td> 562 <p> 563 The character which when preceded by an escape character represents 564 any word character. 565 </p> 566 </td> 567<td> 568 <p> 569 "w" 570 </p> 571 </td> 572</tr> 573<tr> 574<td> 575 <p> 576 123 577 </p> 578 </td> 579<td> 580 <p> 581 The character which when preceded by an escape character represents 582 a non-word character. 583 </p> 584 </td> 585<td> 586 <p> 587 "W" 588 </p> 589 </td> 590</tr> 591<tr> 592<td> 593 <p> 594 124 595 </p> 596 </td> 597<td> 598 <p> 599 The character which when preceded by an escape character represents 600 a start of buffer assertion. 601 </p> 602 </td> 603<td> 604 <p> 605 "`A" 606 </p> 607 </td> 608</tr> 609<tr> 610<td> 611 <p> 612 125 613 </p> 614 </td> 615<td> 616 <p> 617 The character which when preceded by an escape character represents 618 an end of buffer assertion. 619 </p> 620 </td> 621<td> 622 <p> 623 "'z" 624 </p> 625 </td> 626</tr> 627<tr> 628<td> 629 <p> 630 126 631 </p> 632 </td> 633<td> 634 <p> 635 The newline character. 636 </p> 637 </td> 638<td> 639 <p> 640 "\n" 641 </p> 642 </td> 643</tr> 644<tr> 645<td> 646 <p> 647 127 648 </p> 649 </td> 650<td> 651 <p> 652 The comma separator. 653 </p> 654 </td> 655<td> 656 <p> 657 "," 658 </p> 659 </td> 660</tr> 661<tr> 662<td> 663 <p> 664 128 665 </p> 666 </td> 667<td> 668 <p> 669 The character which when preceded by an escape character represents 670 the bell character. 671 </p> 672 </td> 673<td> 674 <p> 675 "a" 676 </p> 677 </td> 678</tr> 679<tr> 680<td> 681 <p> 682 129 683 </p> 684 </td> 685<td> 686 <p> 687 The character which when preceded by an escape character represents 688 the form feed character. 689 </p> 690 </td> 691<td> 692 <p> 693 "f" 694 </p> 695 </td> 696</tr> 697<tr> 698<td> 699 <p> 700 130 701 </p> 702 </td> 703<td> 704 <p> 705 The character which when preceded by an escape character represents 706 the newline character. 707 </p> 708 </td> 709<td> 710 <p> 711 "n" 712 </p> 713 </td> 714</tr> 715<tr> 716<td> 717 <p> 718 131 719 </p> 720 </td> 721<td> 722 <p> 723 The character which when preceded by an escape character represents 724 the carriage return character. 725 </p> 726 </td> 727<td> 728 <p> 729 "r" 730 </p> 731 </td> 732</tr> 733<tr> 734<td> 735 <p> 736 132 737 </p> 738 </td> 739<td> 740 <p> 741 The character which when preceded by an escape character represents 742 the tab character. 743 </p> 744 </td> 745<td> 746 <p> 747 "t" 748 </p> 749 </td> 750</tr> 751<tr> 752<td> 753 <p> 754 133 755 </p> 756 </td> 757<td> 758 <p> 759 The character which when preceded by an escape character represents 760 the vertical tab character. 761 </p> 762 </td> 763<td> 764 <p> 765 "v" 766 </p> 767 </td> 768</tr> 769<tr> 770<td> 771 <p> 772 134 773 </p> 774 </td> 775<td> 776 <p> 777 The character which when preceded by an escape character represents 778 the start of a hexadecimal character constant. 779 </p> 780 </td> 781<td> 782 <p> 783 "x" 784 </p> 785 </td> 786</tr> 787<tr> 788<td> 789 <p> 790 135 791 </p> 792 </td> 793<td> 794 <p> 795 The character which when preceded by an escape character represents 796 the start of an ASCII escape character. 797 </p> 798 </td> 799<td> 800 <p> 801 "c" 802 </p> 803 </td> 804</tr> 805<tr> 806<td> 807 <p> 808 136 809 </p> 810 </td> 811<td> 812 <p> 813 The colon character. 814 </p> 815 </td> 816<td> 817 <p> 818 ":" 819 </p> 820 </td> 821</tr> 822<tr> 823<td> 824 <p> 825 137 826 </p> 827 </td> 828<td> 829 <p> 830 The equals character. 831 </p> 832 </td> 833<td> 834 <p> 835 "=" 836 </p> 837 </td> 838</tr> 839<tr> 840<td> 841 <p> 842 138 843 </p> 844 </td> 845<td> 846 <p> 847 The character which when preceded by an escape character represents 848 the ASCII escape character. 849 </p> 850 </td> 851<td> 852 <p> 853 "e" 854 </p> 855 </td> 856</tr> 857<tr> 858<td> 859 <p> 860 139 861 </p> 862 </td> 863<td> 864 <p> 865 The character which when preceded by an escape character represents 866 any lower case character. 867 </p> 868 </td> 869<td> 870 <p> 871 "l" 872 </p> 873 </td> 874</tr> 875<tr> 876<td> 877 <p> 878 140 879 </p> 880 </td> 881<td> 882 <p> 883 The character which when preceded by an escape character represents 884 any non-lower case character. 885 </p> 886 </td> 887<td> 888 <p> 889 "L" 890 </p> 891 </td> 892</tr> 893<tr> 894<td> 895 <p> 896 141 897 </p> 898 </td> 899<td> 900 <p> 901 The character which when preceded by an escape character represents 902 any upper case character. 903 </p> 904 </td> 905<td> 906 <p> 907 "u" 908 </p> 909 </td> 910</tr> 911<tr> 912<td> 913 <p> 914 142 915 </p> 916 </td> 917<td> 918 <p> 919 The character which when preceded by an escape character represents 920 any non-upper case character. 921 </p> 922 </td> 923<td> 924 <p> 925 "U" 926 </p> 927 </td> 928</tr> 929<tr> 930<td> 931 <p> 932 143 933 </p> 934 </td> 935<td> 936 <p> 937 The character which when preceded by an escape character represents 938 any space character. 939 </p> 940 </td> 941<td> 942 <p> 943 "s" 944 </p> 945 </td> 946</tr> 947<tr> 948<td> 949 <p> 950 144 951 </p> 952 </td> 953<td> 954 <p> 955 The character which when preceded by an escape character represents 956 any non-space character. 957 </p> 958 </td> 959<td> 960 <p> 961 "S" 962 </p> 963 </td> 964</tr> 965<tr> 966<td> 967 <p> 968 145 969 </p> 970 </td> 971<td> 972 <p> 973 The character which when preceded by an escape character represents 974 any digit character. 975 </p> 976 </td> 977<td> 978 <p> 979 "d" 980 </p> 981 </td> 982</tr> 983<tr> 984<td> 985 <p> 986 146 987 </p> 988 </td> 989<td> 990 <p> 991 The character which when preceded by an escape character represents 992 any non-digit character. 993 </p> 994 </td> 995<td> 996 <p> 997 "D" 998 </p> 999 </td> 1000</tr> 1001<tr> 1002<td> 1003 <p> 1004 147 1005 </p> 1006 </td> 1007<td> 1008 <p> 1009 The character which when preceded by an escape character represents 1010 the end quote operator. 1011 </p> 1012 </td> 1013<td> 1014 <p> 1015 "E" 1016 </p> 1017 </td> 1018</tr> 1019<tr> 1020<td> 1021 <p> 1022 148 1023 </p> 1024 </td> 1025<td> 1026 <p> 1027 The character which when preceded by an escape character represents 1028 the start quote operator. 1029 </p> 1030 </td> 1031<td> 1032 <p> 1033 "Q" 1034 </p> 1035 </td> 1036</tr> 1037<tr> 1038<td> 1039 <p> 1040 149 1041 </p> 1042 </td> 1043<td> 1044 <p> 1045 The character which when preceded by an escape character represents 1046 a Unicode combining character sequence. 1047 </p> 1048 </td> 1049<td> 1050 <p> 1051 "X" 1052 </p> 1053 </td> 1054</tr> 1055<tr> 1056<td> 1057 <p> 1058 150 1059 </p> 1060 </td> 1061<td> 1062 <p> 1063 The character which when preceded by an escape character represents 1064 any single character. 1065 </p> 1066 </td> 1067<td> 1068 <p> 1069 "C" 1070 </p> 1071 </td> 1072</tr> 1073<tr> 1074<td> 1075 <p> 1076 151 1077 </p> 1078 </td> 1079<td> 1080 <p> 1081 The character which when preceded by an escape character represents 1082 end of buffer operator. 1083 </p> 1084 </td> 1085<td> 1086 <p> 1087 "Z" 1088 </p> 1089 </td> 1090</tr> 1091<tr> 1092<td> 1093 <p> 1094 152 1095 </p> 1096 </td> 1097<td> 1098 <p> 1099 The character which when preceded by an escape character represents 1100 the continuation assertion. 1101 </p> 1102 </td> 1103<td> 1104 <p> 1105 "G" 1106 </p> 1107 </td> 1108</tr> 1109<tr> 1110<td> 1111 <p> 1112 153 1113 </p> 1114 </td> 1115<td> 1116 <p> 1117 The character which when preceded by (? indicates a zero width 1118 negated forward lookahead assert. 1119 </p> 1120 </td> 1121<td> 1122 <p> 1123 ! 1124 </p> 1125 </td> 1126</tr> 1127</tbody> 1128</table></div> 1129<p> 1130 Custom error messages are loaded as follows: 1131 </p> 1132<div class="informaltable"><table class="table"> 1133<colgroup> 1134<col> 1135<col> 1136<col> 1137</colgroup> 1138<thead><tr> 1139<th> 1140 <p> 1141 Message ID 1142 </p> 1143 </th> 1144<th> 1145 <p> 1146 Error message ID 1147 </p> 1148 </th> 1149<th> 1150 <p> 1151 Default string 1152 </p> 1153 </th> 1154</tr></thead> 1155<tbody> 1156<tr> 1157<td> 1158 <p> 1159 201 1160 </p> 1161 </td> 1162<td> 1163 <p> 1164 REG_NOMATCH 1165 </p> 1166 </td> 1167<td> 1168 <p> 1169 "No match" 1170 </p> 1171 </td> 1172</tr> 1173<tr> 1174<td> 1175 <p> 1176 202 1177 </p> 1178 </td> 1179<td> 1180 <p> 1181 REG_BADPAT 1182 </p> 1183 </td> 1184<td> 1185 <p> 1186 "Invalid regular expression" 1187 </p> 1188 </td> 1189</tr> 1190<tr> 1191<td> 1192 <p> 1193 203 1194 </p> 1195 </td> 1196<td> 1197 <p> 1198 REG_ECOLLATE 1199 </p> 1200 </td> 1201<td> 1202 <p> 1203 "Invalid collation character" 1204 </p> 1205 </td> 1206</tr> 1207<tr> 1208<td> 1209 <p> 1210 204 1211 </p> 1212 </td> 1213<td> 1214 <p> 1215 REG_ECTYPE 1216 </p> 1217 </td> 1218<td> 1219 <p> 1220 "Invalid character class name" 1221 </p> 1222 </td> 1223</tr> 1224<tr> 1225<td> 1226 <p> 1227 205 1228 </p> 1229 </td> 1230<td> 1231 <p> 1232 REG_EESCAPE 1233 </p> 1234 </td> 1235<td> 1236 <p> 1237 "Trailing backslash" 1238 </p> 1239 </td> 1240</tr> 1241<tr> 1242<td> 1243 <p> 1244 206 1245 </p> 1246 </td> 1247<td> 1248 <p> 1249 REG_ESUBREG 1250 </p> 1251 </td> 1252<td> 1253 <p> 1254 "Invalid back reference" 1255 </p> 1256 </td> 1257</tr> 1258<tr> 1259<td> 1260 <p> 1261 207 1262 </p> 1263 </td> 1264<td> 1265 <p> 1266 REG_EBRACK 1267 </p> 1268 </td> 1269<td> 1270 <p> 1271 "Unmatched [ or [^" 1272 </p> 1273 </td> 1274</tr> 1275<tr> 1276<td> 1277 <p> 1278 208 1279 </p> 1280 </td> 1281<td> 1282 <p> 1283 REG_EPAREN 1284 </p> 1285 </td> 1286<td> 1287 <p> 1288 "Unmatched ( or \(" 1289 </p> 1290 </td> 1291</tr> 1292<tr> 1293<td> 1294 <p> 1295 209 1296 </p> 1297 </td> 1298<td> 1299 <p> 1300 REG_EBRACE 1301 </p> 1302 </td> 1303<td> 1304 <p> 1305 "Unmatched \{" 1306 </p> 1307 </td> 1308</tr> 1309<tr> 1310<td> 1311 <p> 1312 210 1313 </p> 1314 </td> 1315<td> 1316 <p> 1317 REG_BADBR 1318 </p> 1319 </td> 1320<td> 1321 <p> 1322 "Invalid content of \{\}" 1323 </p> 1324 </td> 1325</tr> 1326<tr> 1327<td> 1328 <p> 1329 211 1330 </p> 1331 </td> 1332<td> 1333 <p> 1334 REG_ERANGE 1335 </p> 1336 </td> 1337<td> 1338 <p> 1339 "Invalid range end" 1340 </p> 1341 </td> 1342</tr> 1343<tr> 1344<td> 1345 <p> 1346 212 1347 </p> 1348 </td> 1349<td> 1350 <p> 1351 REG_ESPACE 1352 </p> 1353 </td> 1354<td> 1355 <p> 1356 "Memory exhausted" 1357 </p> 1358 </td> 1359</tr> 1360<tr> 1361<td> 1362 <p> 1363 213 1364 </p> 1365 </td> 1366<td> 1367 <p> 1368 REG_BADRPT 1369 </p> 1370 </td> 1371<td> 1372 <p> 1373 "Invalid preceding regular expression" 1374 </p> 1375 </td> 1376</tr> 1377<tr> 1378<td> 1379 <p> 1380 214 1381 </p> 1382 </td> 1383<td> 1384 <p> 1385 REG_EEND 1386 </p> 1387 </td> 1388<td> 1389 <p> 1390 "Premature end of regular expression" 1391 </p> 1392 </td> 1393</tr> 1394<tr> 1395<td> 1396 <p> 1397 215 1398 </p> 1399 </td> 1400<td> 1401 <p> 1402 REG_ESIZE 1403 </p> 1404 </td> 1405<td> 1406 <p> 1407 "Regular expression too big" 1408 </p> 1409 </td> 1410</tr> 1411<tr> 1412<td> 1413 <p> 1414 216 1415 </p> 1416 </td> 1417<td> 1418 <p> 1419 REG_ERPAREN 1420 </p> 1421 </td> 1422<td> 1423 <p> 1424 "Unmatched ) or \)" 1425 </p> 1426 </td> 1427</tr> 1428<tr> 1429<td> 1430 <p> 1431 217 1432 </p> 1433 </td> 1434<td> 1435 <p> 1436 REG_EMPTY 1437 </p> 1438 </td> 1439<td> 1440 <p> 1441 "Empty expression" 1442 </p> 1443 </td> 1444</tr> 1445<tr> 1446<td> 1447 <p> 1448 218 1449 </p> 1450 </td> 1451<td> 1452 <p> 1453 REG_E_UNKNOWN 1454 </p> 1455 </td> 1456<td> 1457 <p> 1458 "Unknown error" 1459 </p> 1460 </td> 1461</tr> 1462</tbody> 1463</table></div> 1464<p> 1465 Custom character class names are loaded as followed: 1466 </p> 1467<div class="informaltable"><table class="table"> 1468<colgroup> 1469<col> 1470<col> 1471<col> 1472</colgroup> 1473<thead><tr> 1474<th> 1475 <p> 1476 Message ID 1477 </p> 1478 </th> 1479<th> 1480 <p> 1481 Description 1482 </p> 1483 </th> 1484<th> 1485 <p> 1486 Equivalent default class name 1487 </p> 1488 </th> 1489</tr></thead> 1490<tbody> 1491<tr> 1492<td> 1493 <p> 1494 300 1495 </p> 1496 </td> 1497<td> 1498 <p> 1499 The character class name for alphanumeric characters. 1500 </p> 1501 </td> 1502<td> 1503 <p> 1504 "alnum" 1505 </p> 1506 </td> 1507</tr> 1508<tr> 1509<td> 1510 <p> 1511 301 1512 </p> 1513 </td> 1514<td> 1515 <p> 1516 The character class name for alphabetic characters. 1517 </p> 1518 </td> 1519<td> 1520 <p> 1521 "alpha" 1522 </p> 1523 </td> 1524</tr> 1525<tr> 1526<td> 1527 <p> 1528 302 1529 </p> 1530 </td> 1531<td> 1532 <p> 1533 The character class name for control characters. 1534 </p> 1535 </td> 1536<td> 1537 <p> 1538 "cntrl" 1539 </p> 1540 </td> 1541</tr> 1542<tr> 1543<td> 1544 <p> 1545 303 1546 </p> 1547 </td> 1548<td> 1549 <p> 1550 The character class name for digit characters. 1551 </p> 1552 </td> 1553<td> 1554 <p> 1555 "digit" 1556 </p> 1557 </td> 1558</tr> 1559<tr> 1560<td> 1561 <p> 1562 304 1563 </p> 1564 </td> 1565<td> 1566 <p> 1567 The character class name for graphics characters. 1568 </p> 1569 </td> 1570<td> 1571 <p> 1572 "graph" 1573 </p> 1574 </td> 1575</tr> 1576<tr> 1577<td> 1578 <p> 1579 305 1580 </p> 1581 </td> 1582<td> 1583 <p> 1584 The character class name for lower case characters. 1585 </p> 1586 </td> 1587<td> 1588 <p> 1589 "lower" 1590 </p> 1591 </td> 1592</tr> 1593<tr> 1594<td> 1595 <p> 1596 306 1597 </p> 1598 </td> 1599<td> 1600 <p> 1601 The character class name for printable characters. 1602 </p> 1603 </td> 1604<td> 1605 <p> 1606 "print" 1607 </p> 1608 </td> 1609</tr> 1610<tr> 1611<td> 1612 <p> 1613 307 1614 </p> 1615 </td> 1616<td> 1617 <p> 1618 The character class name for punctuation characters. 1619 </p> 1620 </td> 1621<td> 1622 <p> 1623 "punct" 1624 </p> 1625 </td> 1626</tr> 1627<tr> 1628<td> 1629 <p> 1630 308 1631 </p> 1632 </td> 1633<td> 1634 <p> 1635 The character class name for space characters. 1636 </p> 1637 </td> 1638<td> 1639 <p> 1640 "space" 1641 </p> 1642 </td> 1643</tr> 1644<tr> 1645<td> 1646 <p> 1647 309 1648 </p> 1649 </td> 1650<td> 1651 <p> 1652 The character class name for upper case characters. 1653 </p> 1654 </td> 1655<td> 1656 <p> 1657 "upper" 1658 </p> 1659 </td> 1660</tr> 1661<tr> 1662<td> 1663 <p> 1664 310 1665 </p> 1666 </td> 1667<td> 1668 <p> 1669 The character class name for hexadecimal characters. 1670 </p> 1671 </td> 1672<td> 1673 <p> 1674 "xdigit" 1675 </p> 1676 </td> 1677</tr> 1678<tr> 1679<td> 1680 <p> 1681 311 1682 </p> 1683 </td> 1684<td> 1685 <p> 1686 The character class name for blank characters. 1687 </p> 1688 </td> 1689<td> 1690 <p> 1691 "blank" 1692 </p> 1693 </td> 1694</tr> 1695<tr> 1696<td> 1697 <p> 1698 312 1699 </p> 1700 </td> 1701<td> 1702 <p> 1703 The character class name for word characters. 1704 </p> 1705 </td> 1706<td> 1707 <p> 1708 "word" 1709 </p> 1710 </td> 1711</tr> 1712<tr> 1713<td> 1714 <p> 1715 313 1716 </p> 1717 </td> 1718<td> 1719 <p> 1720 The character class name for Unicode characters. 1721 </p> 1722 </td> 1723<td> 1724 <p> 1725 "unicode" 1726 </p> 1727 </td> 1728</tr> 1729</tbody> 1730</table></div> 1731<p> 1732 Finally, custom collating element names are loaded starting from message 1733 id 400, and terminating when the first load thereafter fails. Each message 1734 looks something like: "tagname string" where tagname is the name 1735 used inside [[.tagname.]] and string is the actual text of the collating 1736 element. Note that the value of collating element [[.zero.]] is used for 1737 the conversion of strings to numbers - if you replace this with another value 1738 then that will be used for string parsing - for example use the Unicode character 1739 0x0660 for [[.zero.]] if you want to use Unicode Arabic-Indic digits in your 1740 regular expressions in place of Latin digits. 1741 </p> 1742<p> 1743 Note that the POSIX defined names for character classes and collating elements 1744 are always available - even if custom names are defined, in contrast, custom 1745 error messages, and custom syntax messages replace the default ones. 1746 </p> 1747</div> 1748<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 1749<td align="left"></td> 1750<td align="right"><div class="copyright-footer">Copyright © 1998-2013 John Maddock<p> 1751 Distributed under the Boost Software License, Version 1.0. (See accompanying 1752 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>) 1753 </p> 1754</div></td> 1755</tr></table> 1756<hr> 1757<div class="spirit-nav"> 1758<a accesskey="p" href="headers.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../background.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="thread_safety.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 1759</div> 1760</body> 1761</html> 1762
