src/Lexer.cpp

   1 /**
   2  * \file Lexer.cpp
   3  * This file is part of LyX, the document processor.
   4  * Licence details can be found in the file COPYING.
   5  *
   6  * \author Alejandro Aguilar Sierra
   7  * \author Lars Gullik Bjønnes
   8  * \author Jean-Marc Lasgouttes
   9  * \author John Levon
  10  *
  11  * Full author contact details are available in file CREDITS.
  12  */
  13
  14 #include <config.h>
  15
  16 #include "Lexer.h"
  17
  18 #include "support/convert.h"
  19 #include "support/debug.h"
  20 #include "support/FileName.h"
  21 #include "support/filetools.h"
  22 #include "support/gzstream.h"
  23 #include "support/lassert.h"
  24 #include "support/lstrings.h"
  25 #include "support/lyxalgo.h"
  26 #include "support/types.h"
  27
  28 #include <functional>
  29 #include <istream>
  30 #include <stack>
  31 #include <vector>
  32
  33 using namespace std;
  34 using namespace lyx::support;
  35
  36 namespace lyx {
  37
  38 //////////////////////////////////////////////////////////////////////
  39 //
  40 // Lexer::Pimpl
  41 //
  42 //////////////////////////////////////////////////////////////////////
  43
  44
  45 ///
  46 class Lexer::Pimpl {
  47 public:
  48         ///
  49         Pimpl(LexerKeyword * tab, int num);
  50         ///
  51         string const getString() const;
  52         ///
  53         docstring const getDocString() const;
  54         ///
  55         void printError(string const & message) const;
  56         ///
  57         void printTable(ostream & os);
  58         ///
  59         void pushTable(LexerKeyword * tab, int num);
  60         ///
  61         void popTable();
  62         ///
  63         bool setFile(FileName const & filename);
  64         ///
  65         void setStream(istream & i);
  66         ///
  67         void setCommentChar(char c);
  68         ///
  69         bool next(bool esc = false);
  70         ///
  71         int searchKeyword(char const * const tag) const;
  72         ///
  73         int lex();
  74         ///
  75         bool eatLine();
  76         ///
  77         bool nextToken();
  78         /// test if there is a pushed token or the stream is ok
  79         bool inputAvailable();
  80         ///
  81         void pushToken(string const &);
  82         /// fb_ is only used to open files, the stream is accessed through is.
  83         filebuf fb_;
  84
  85         /// gz_ is only used to open files, the stream is accessed through is.
  86         gz::gzstreambuf gz_;
  87
  88         /// the stream that we use.
  89         istream is;
  90         ///
  91         string name;
  92         ///
  93         LexerKeyword * table;
  94         ///
  95         int no_items;
  96         ///
  97         string buff;
  98         ///
  99         int status;
 100         ///
 101         int lineno;
 102         ///
 103         string pushTok;
 104         ///
 105         char commentChar;
 106         /// used for error messages
 107         string context;
 108 private:
 109         /// non-copyable
 110         Pimpl(Pimpl const &);
 111         void operator=(Pimpl const &);
 112
 113         ///
 114         void verifyTable();
 115         ///
 116         class PushedTable {
 117         public:
 118                 ///
 119                 PushedTable()
 120                         : table_elem(0), table_siz(0) {}
 121                 ///
 122                 PushedTable(LexerKeyword * ki, int siz)
 123                         : table_elem(ki), table_siz(siz) {}
 124                 ///
 125                 LexerKeyword * table_elem;
 126                 ///
 127                 int table_siz;
 128         };
 129         ///
 130         stack<PushedTable> pushed;
 131 };
 132
 133
 134
 135 namespace {
 136
 137 class CompareTags
 138         : public binary_function<LexerKeyword, LexerKeyword, bool> {
 139 public:
 140         // used by lower_bound, sort and sorted
 141         bool operator()(LexerKeyword const & a, LexerKeyword const & b) const
 142         {
 143                 // we use the ascii version, because in turkish, 'i'
 144                 // is not the lowercase version of 'I', and thus
 145                 // turkish locale breaks parsing of tags.
 146                 return compare_ascii_no_case(a.tag, b.tag) < 0;
 147         }
 148 };
 149
 150 } // end of anon namespace
 151
 152
 153 Lexer::Pimpl::Pimpl(LexerKeyword * tab, int num)
 154         : is(&fb_), table(tab), no_items(num),
 155           status(0), lineno(0), commentChar('#')
 156 {
 157         verifyTable();
 158 }
 159
 160
 161 string const Lexer::Pimpl::getString() const
 162 {
 163         return buff;
 164 }
 165
 166
 167 docstring const Lexer::Pimpl::getDocString() const
 168 {
 169         return from_utf8(buff);
 170 }
 171
 172
 173 void Lexer::Pimpl::printError(string const & message) const
 174 {
 175         string const tmpmsg = subst(message, "$$Token", getString());
 176         lyxerr << "LyX: " << tmpmsg << " [around line " << lineno
 177                 << " of file " << to_utf8(makeDisplayPath(name))
 178                 << " current token: '" << getString() << "'"
 179                 << " context: '" << context << "']" << endl;
 180 }
 181
 182
 183 void Lexer::Pimpl::printTable(ostream & os)
 184 {
 185         os << "\nNumber of tags: " << no_items << endl;
 186         for (int i= 0; i < no_items; ++i)
 187                 os << "table[" << i
 188                    << "]:  tag: `" << table[i].tag
 189                    << "'  code:" << table[i].code << '\n';
 190         os.flush();
 191 }
 192
 193
 194 void Lexer::Pimpl::verifyTable()
 195 {
 196         // Check if the table is sorted and if not, sort it.
 197         if (table
 198             && !lyx::sorted(table, table + no_items, CompareTags())) {
 199                 lyxerr << "The table passed to Lexer is not sorted!\n"
 200                        << "Tell the developers to fix it!" << endl;
 201                 // We sort it anyway to avoid problems.
 202                 lyxerr << "\nUnsorted:" << endl;
 203                 printTable(lyxerr);
 204
 205                 sort(table, table + no_items, CompareTags());
 206                 lyxerr << "\nSorted:" << endl;
 207                 printTable(lyxerr);
 208         }
 209 }
 210
 211
 212 void Lexer::Pimpl::pushTable(LexerKeyword * tab, int num)
 213 {
 214         PushedTable tmppu(table, no_items);
 215         pushed.push(tmppu);
 216
 217         table = tab;
 218         no_items = num;
 219
 220         verifyTable();
 221 }
 222
 223
 224 void Lexer::Pimpl::popTable()
 225 {
 226         if (pushed.empty()) {
 227                 lyxerr << "Lexer error: nothing to pop!" << endl;
 228                 return;
 229         }
 230
 231         PushedTable tmp = pushed.top();
 232         pushed.pop();
 233         table = tmp.table_elem;
 234         no_items = tmp.table_siz;
 235 }
 236
 237
 238 bool Lexer::Pimpl::setFile(FileName const & filename)
 239 {
 240         // Check the format of the file.
 241         string const format = filename.guessFormatFromContents();
 242
 243         if (format == "gzip" || format == "zip" || format == "compress") {
 244                 LYXERR(Debug::LYXLEX, "lyxlex: compressed");
 245                 // The check only outputs a debug message, because it triggers
 246                 // a bug in compaq cxx 6.2, where is_open() returns 'true' for
 247                 // a fresh new filebuf.  (JMarc)
 248                 if (gz_.is_open() || istream::off_type(is.tellg()) > -1)
 249                         LYXERR(Debug::LYXLEX, "Error in LyXLex::setFile: "
 250                                 "file or stream already set.");
 251                 gz_.open(filename.toFilesystemEncoding().c_str(), ios::in);
 252                 is.rdbuf(&gz_);
 253                 name = filename.absFilename();
 254                 lineno = 0;
 255                 if (!gz_.is_open() || !is.good())
 256                         return false;
 257         } else {
 258                 LYXERR(Debug::LYXLEX, "lyxlex: UNcompressed");
 259
 260                 // The check only outputs a debug message, because it triggers
 261                 // a bug in compaq cxx 6.2, where is_open() returns 'true' for
 262                 // a fresh new filebuf.  (JMarc)
 263                 if (fb_.is_open() || istream::off_type(is.tellg()) > 0) {
 264                         LYXERR(Debug::LYXLEX, "Error in Lexer::setFile: "
 265                                 "file or stream already set.");
 266                 }
 267                 fb_.open(filename.toFilesystemEncoding().c_str(), ios::in);
 268                 is.rdbuf(&fb_);
 269                 name = filename.absFilename();
 270                 lineno = 0;
 271                 if (!fb_.is_open() || !is.good())
 272                         return false;
 273         }
 274
 275         // Skip byte order mark.
 276         if (is.peek() == 0xef) {
 277                 int c = is.get();
 278                 if (is.peek() == 0xbb) {
 279                         c = is.get();
 280                         LASSERT(is.get() == 0xbf, /**/);
 281                 } else
 282                         is.unget();
 283         }
 284
 285         return true;
 286 }
 287
 288
 289 void Lexer::Pimpl::setStream(istream & i)
 290 {
 291         if (fb_.is_open() || istream::off_type(is.tellg()) > 0) {
 292                 LYXERR(Debug::LYXLEX, "Error in Lexer::setStream: "
 293                         "file or stream already set.");
 294         }
 295         is.rdbuf(i.rdbuf());
 296         lineno = 0;
 297 }
 298
 299
 300 void Lexer::Pimpl::setCommentChar(char c)
 301 {
 302         commentChar = c;
 303 }
 304
 305
 306 bool Lexer::Pimpl::next(bool esc /* = false */)
 307 {
 308         if (!pushTok.empty()) {
 309                 // There can have been a whole line pushed so
 310                 // we extract the first word and leaves the rest
 311                 // in pushTok. (Lgb)
 312                 if (pushTok[0] == '\\' && pushTok.find(' ') != string::npos) {
 313                         buff.clear();
 314                         pushTok = split(pushTok, buff, ' ');
 315                 } else {
 316                         buff = pushTok;
 317                         pushTok.clear();
 318                 }
 319                 status = LEX_TOKEN;
 320                 return true;
 321         }
 322
 323
 324         unsigned char c = 0; // getc() returns an int
 325         char cc = 0;
 326         status = 0;
 327         while (is && !status) {
 328                 is.get(cc);
 329                 c = cc;
 330
 331                 if (c == commentChar) {
 332                         // Read rest of line (fast :-)
 333 #if 1
 334                         // That is not fast... (Lgb)
 335                         string dummy;
 336                         getline(is, dummy);
 337
 338                         LYXERR(Debug::LYXLEX, "Comment read: `" << c << dummy << '\'');
 339 #else
 340                         // unfortunately ignore is buggy (Lgb)
 341                         is.ignore(100, '\n');
 342 #endif
 343                         ++lineno;
 344                         continue;
 345                 }
 346
 347                 if (c == '\"') {
 348                         buff.clear();
 349
 350                         if (esc) {
 351
 352                                 bool escaped = false;
 353                                 do {
 354                                         escaped = false;
 355                                         is.get(cc);
 356                                         c = cc;
 357                                         if (c == '\r') continue;
 358                                         if (c == '\\') {
 359                                                 // escape the next char
 360                                                 is.get(cc);
 361                                                 c = cc;
 362                                                 if (c == '\"' || c == '\\')
 363                                                         escaped = true;
 364                                                 else
 365                                                         buff.push_back('\\');
 366                                         }
 367                                         buff.push_back(c);
 368
 369                                         if (!escaped && c == '\"')
 370                                                 break;
 371                                 } while (c != '\n' && is);
 372
 373                         } else {
 374
 375                                 do {
 376                                         is.get(cc);
 377                                         c = cc;
 378                                         if (c != '\r')
 379                                                 buff.push_back(c);
 380                                 } while (c != '\"' && c != '\n' && is);
 381
 382                         }
 383
 384                         if (c != '\"') {
 385                                 printError("Missing quote");
 386                                 if (c == '\n')
 387                                         ++lineno;
 388                         }
 389
 390                         buff.resize(buff.size() - 1);
 391                         status = LEX_DATA;
 392                         break;
 393                 }
 394
 395                 if (c == ',')
 396                         continue;              /* Skip ','s */
 397
 398                 // using relational operators with chars other
 399                 // than == and != is not safe. And if it is done
 400                 // the type _have_ to be unsigned. It usually a
 401                 // lot better to use the functions from cctype
 402                 if (c > ' ' && is)  {
 403                         buff.clear();
 404
 405                         do {
 406                                 if (esc && c == '\\') {
 407                                         // escape the next char
 408                                         is.get(cc);
 409                                         c = cc;
 410                                         //escaped = true;
 411                                 }
 412                                 buff.push_back(c);
 413                                 is.get(cc);
 414                                 c = cc;
 415                         } while (c > ' ' && c != ',' && is);
 416                         status = LEX_TOKEN;
 417                 }
 418
 419                 if (c == '\r' && is) {
 420                         // The Windows support has lead to the
 421                         // possibility of "\r\n" at the end of
 422                         // a line.  This will stop LyX choking
 423                         // when it expected to find a '\n'
 424                         is.get(cc);
 425                         c = cc;
 426                 }
 427
 428                 if (c == '\n')
 429                         ++lineno;
 430
 431         }
 432         if (status)
 433                 return true;
 434
 435         status = is.eof() ? LEX_FEOF: LEX_UNDEF;
 436         buff.clear();
 437         return false;
 438 }
 439
 440
 441 int Lexer::Pimpl::searchKeyword(char const * const tag) const
 442 {
 443         LexerKeyword search_tag = { tag, 0 };
 444         LexerKeyword * res =
 445                 lower_bound(table, table + no_items,
 446                             search_tag, CompareTags());
 447         // use the compare_ascii_no_case instead of compare_no_case,
 448         // because in turkish, 'i' is not the lowercase version of 'I',
 449         // and thus turkish locale breaks parsing of tags.
 450         if (res != table + no_items
 451             && !compare_ascii_no_case(res->tag, tag))
 452                 return res->code;
 453         return LEX_UNDEF;
 454 }
 455
 456
 457 int Lexer::Pimpl::lex()
 458 {
 459         //NOTE: possible bug.
 460         if (next() && status == LEX_TOKEN)
 461                 return searchKeyword(getString().c_str());
 462         return status;
 463 }
 464
 465
 466 bool Lexer::Pimpl::eatLine()
 467 {
 468         buff.clear();
 469
 470         unsigned char c = '\0';
 471         char cc = 0;
 472         while (is && c != '\n') {
 473                 is.get(cc);
 474                 c = cc;
 475                 //LYXERR(Debug::LYXLEX, "Lexer::EatLine read char: `" << c << '\'');
 476                 if (c != '\r')
 477                         buff.push_back(c);
 478         }
 479
 480         if (c == '\n') {
 481                 ++lineno;
 482                 buff.resize(buff.size() - 1);
 483                 status = LEX_DATA;
 484                 return true;
 485         } else if (buff.length() > 0) { // last line
 486                 status = LEX_DATA;
 487                 return true;
 488         } else {
 489                 return false;
 490         }
 491 }
 492
 493
 494 bool Lexer::Pimpl::nextToken()
 495 {
 496         if (!pushTok.empty()) {
 497                 // There can have been a whole line pushed so
 498                 // we extract the first word and leaves the rest
 499                 // in pushTok. (Lgb)
 500                 if (pushTok[0] == '\\' && pushTok.find(' ') != string::npos) {
 501                         buff.clear();
 502                         pushTok = split(pushTok, buff, ' ');
 503                 } else {
 504                         buff = pushTok;
 505                         pushTok.clear();
 506                 }
 507                 status = LEX_TOKEN;
 508                 return true;
 509         }
 510
 511         status = 0;
 512         while (is && !status) {
 513                 unsigned char c = 0;
 514                 char cc = 0;
 515                 is.get(cc);
 516                 c = cc;
 517                 if ((c >= ' ' || c == '\t') && is) {
 518                         buff.clear();
 519
 520                         if (c == '\\') { // first char == '\\'
 521                                 do {
 522                                         buff.push_back(c);
 523                                         is.get(cc);
 524                                         c = cc;
 525                                 } while (c > ' ' && c != '\\' && is);
 526                         } else {
 527                                 do {
 528                                         buff.push_back(c);
 529                                         is.get(cc);
 530                                         c = cc;
 531                                 } while ((c >= ' ' || c == '\t') && c != '\\' && is);
 532                         }
 533
 534                         if (c == '\\')
 535                                 is.putback(c); // put it back
 536                         status = LEX_TOKEN;
 537                 }
 538
 539                 if (c == '\n')
 540                         ++lineno;
 541
 542         }
 543         if (status)
 544                 return true;
 545
 546         status = is.eof() ? LEX_FEOF: LEX_UNDEF;
 547         buff.clear();
 548         return false;
 549 }
 550
 551
 552 bool Lexer::Pimpl::inputAvailable()
 553 {
 554         return is.good();
 555 }
 556
 557
 558 void Lexer::Pimpl::pushToken(string const & pt)
 559 {
 560         pushTok = pt;
 561 }
 562
 563
 564
 565
 566 //////////////////////////////////////////////////////////////////////
 567 //
 568 // Lexer
 569 //
 570 //////////////////////////////////////////////////////////////////////
 571
 572 Lexer::Lexer()
 573         : pimpl_(new Pimpl(0, 0))
 574 {}
 575
 576
 577 void Lexer::init(LexerKeyword * tab, int num)
 578 {
 579          pimpl_ = new Pimpl(tab, num);
 580 }
 581
 582
 583 Lexer::~Lexer()
 584 {
 585         delete pimpl_;
 586 }
 587
 588
 589 bool Lexer::isOK() const
 590 {
 591         return pimpl_->inputAvailable();
 592 }
 593
 594
 595 void Lexer::setLineNumber(int l)
 596 {
 597         pimpl_->lineno = l;
 598 }
 599
 600
 601 int Lexer::lineNumber() const
 602 {
 603         return pimpl_->lineno;
 604 }
 605
 606
 607 istream & Lexer::getStream()
 608 {
 609         return pimpl_->is;
 610 }
 611
 612
 613 void Lexer::pushTable(LexerKeyword * tab, int num)
 614 {
 615         pimpl_->pushTable(tab, num);
 616 }
 617
 618
 619 void Lexer::popTable()
 620 {
 621         pimpl_->popTable();
 622 }
 623
 624
 625 void Lexer::printTable(ostream & os)
 626 {
 627         pimpl_->printTable(os);
 628 }
 629
 630
 631 void Lexer::printError(string const & message) const
 632 {
 633         pimpl_->printError(message);
 634 }
 635
 636
 637 bool Lexer::setFile(FileName const & filename)
 638 {
 639         return pimpl_->setFile(filename);
 640 }
 641
 642
 643 void Lexer::setStream(istream & i)
 644 {
 645         pimpl_->setStream(i);
 646 }
 647
 648
 649 void Lexer::setCommentChar(char c)
 650 {
 651         pimpl_->setCommentChar(c);
 652 }
 653
 654
 655 int Lexer::lex()
 656 {
 657         return pimpl_->lex();
 658 }
 659
 660
 661 int Lexer::getInteger() const
 662 {
 663         lastReadOk_ = pimpl_->status == LEX_DATA || pimpl_->status == LEX_TOKEN;
 664         if (!lastReadOk_) {
 665                 pimpl_->printError("integer token missing");
 666                 return -1;
 667         }
 668
 669         if (isStrInt(pimpl_->getString()))
 670                 return convert<int>(pimpl_->getString());
 671
 672         lastReadOk_ = false;
 673         pimpl_->printError("Bad integer `$$Token'");
 674         return -1;
 675 }
 676
 677
 678 double Lexer::getFloat() const
 679 {
 680         // replace comma with dot in case the file was written with
 681         // the wrong locale (should be rare, but is easy enough to
 682         // avoid).
 683         lastReadOk_ = pimpl_->status == LEX_DATA || pimpl_->status == LEX_TOKEN;
 684         if (!lastReadOk_) {
 685                 pimpl_->printError("float token missing");
 686                 return -1;
 687         }
 688
 689         string const str = subst(pimpl_->getString(), ",", ".");
 690         if (isStrDbl(str))
 691                 return convert<double>(str);
 692
 693         lastReadOk_ = false;
 694         pimpl_->printError("Bad float `$$Token'");
 695         return -1;
 696 }
 697
 698
 699 string const Lexer::getString() const
 700 {
 701         lastReadOk_ = pimpl_->status == LEX_DATA || pimpl_->status == LEX_TOKEN;
 702
 703         if (lastReadOk_)
 704         return pimpl_->getString();
 705
 706         return string();
 707 }
 708
 709
 710 docstring const Lexer::getDocString() const
 711 {
 712         lastReadOk_ = pimpl_->status == LEX_DATA || pimpl_->status == LEX_TOKEN;
 713
 714         if (lastReadOk_)
 715                 return pimpl_->getDocString();
 716
 717         return docstring();
 718 }
 719
 720
 721 // I would prefer to give a tag number instead of an explicit token
 722 // here, but it is not possible because Buffer::readDocument uses
 723 // explicit tokens (JMarc)
 724 string const Lexer::getLongString(string const & endtoken)
 725 {
 726         string str;
 727         string prefix;
 728         bool firstline = true;
 729
 730         while (pimpl_->is) { //< eatLine only reads from is, not from pushTok
 731                 if (!eatLine())
 732                         // blank line in the file being read
 733                         continue;
 734
 735                 string const token = trim(getString(), " \t");
 736
 737                 LYXERR(Debug::PARSER, "LongString: `" << getString() << '\'');
 738
 739                 // We do a case independent comparison, like searchKeyword does.
 740                 if (compare_ascii_no_case(token, endtoken) == 0)
 741                         break;
 742
 743                 string tmpstr = getString();
 744                 if (firstline) {
 745                         size_t i = tmpstr.find_first_not_of(' ');
 746                         if (i != string::npos)
 747                                 prefix = tmpstr.substr(0, i);
 748                         firstline = false;
 749                         LYXERR(Debug::PARSER, "Prefix = `" << prefix << "\'");
 750                 }
 751
 752                 // further lines in long strings may have the same
 753                 // whitespace prefix as the first line. Remove it.
 754                 if (prefix.length() && prefixIs(tmpstr, prefix))
 755                         tmpstr.erase(0, prefix.length() - 1);
 756
 757                 str += ltrim(tmpstr, "\t") + '\n';
 758         }
 759
 760         if (!pimpl_->is)
 761                 printError("Long string not ended by `" + endtoken + '\'');
 762
 763         return str;
 764 }
 765
 766
 767 bool Lexer::getBool() const
 768 {
 769         string const s = pimpl_->getString();
 770         if (s == "false" || s == "0") {
 771                 lastReadOk_ = true;
 772                 return false;
 773         }
 774         if (s == "true" || s == "1") {
 775                 lastReadOk_ = true;
 776                 return true;
 777         }
 778         pimpl_->printError("Bad boolean `$$Token'. "
 779                                  "Use \"false\" or \"true\"");
 780         lastReadOk_ = false;
 781         return false;
 782 }
 783
 784
 785 bool Lexer::eatLine()
 786 {
 787         return pimpl_->eatLine();
 788 }
 789
 790
 791 bool Lexer::next(bool esc)
 792 {
 793         return pimpl_->next(esc);
 794 }
 795
 796
 797 bool Lexer::nextToken()
 798 {
 799         return pimpl_->nextToken();
 800 }
 801
 802
 803 void Lexer::pushToken(string const & pt)
 804 {
 805         pimpl_->pushToken(pt);
 806 }
 807
 808
 809 Lexer::operator void const *() const
 810 {
 811         // This behaviour is NOT the same as the streams which would
 812         // use fail() here. However, our implementation of getString() et al.
 813         // can cause the eof() and fail() bits to be set, even though we
 814         // haven't tried to read 'em.
 815         return lastReadOk_? this : 0;
 816 }
 817
 818
 819 bool Lexer::operator!() const
 820 {
 821         return !lastReadOk_;
 822 }
 823
 824
 825 Lexer & Lexer::operator>>(string & s)
 826 {
 827         if (isOK()) {
 828                 next();
 829                 s = getString();
 830         } else {
 831                 lastReadOk_ = false;
 832         }
 833         return *this;
 834 }
 835
 836
 837 Lexer & Lexer::operator>>(docstring & s)
 838 {
 839         if (isOK()) {
 840                 next();
 841                 s = getDocString();
 842         } else {
 843                 lastReadOk_ = false;
 844         }
 845         return *this;
 846 }
 847
 848
 849 Lexer & Lexer::operator>>(double & s)
 850 {
 851         if (isOK()) {
 852                 next();
 853                 s = getFloat();
 854         } else {
 855                 lastReadOk_ = false;
 856         }
 857         return *this;
 858 }
 859
 860
 861 Lexer & Lexer::operator>>(int & s)
 862 {
 863         if (isOK()) {
 864                 next();
 865                 s = getInteger();
 866         } else {
 867                 lastReadOk_ = false;
 868         }
 869         return *this;
 870 }
 871
 872
 873 Lexer & Lexer::operator>>(unsigned int & s)
 874 {
 875         if (isOK()) {
 876                 next();
 877                 s = getInteger();
 878         } else {
 879                 lastReadOk_ = false;
 880         }
 881         return *this;
 882 }
 883
 884
 885 Lexer & Lexer::operator>>(bool & s)
 886 {
 887         if (isOK()) {
 888                 next();
 889                 s = getBool();
 890         } else {
 891                 lastReadOk_ = false;
 892         }
 893         return *this;
 894 }
 895
 896
 897 Lexer & Lexer::operator>>(char & c)
 898 {
 899         string s;
 900         operator>>(s);
 901         if (!s.empty())
 902                 c = s[0];
 903         return *this;
 904 }
 905
 906
 907 // quotes a string, e.g. for use in preferences files or as an argument
 908 // of the "log" dialog
 909 string Lexer::quoteString(string const & arg)
 910 {
 911         string res;
 912         res += '"';
 913         res += subst(subst(arg, "\\", "\\\\"), "\"", "\\\"");
 914         res += '"';
 915         return res;
 916 }
 917
 918
 919 // same for docstring
 920 docstring Lexer::quoteString(docstring const & arg)
 921 {
 922         docstring res;
 923         res += '"';
 924         res += subst(subst(arg, from_ascii("\\"), from_ascii("\\\\")),
 925                      from_ascii("\""), from_ascii("\\\""));
 926         res += '"';
 927         return res;
 928 }
 929
 930
 931 Lexer & Lexer::operator>>(char const * required)
 932 {
 933         string token;
 934         *this >> token;
 935         if (token != required) {
 936                 LYXERR0("Missing '" << required << "'-tag in " << pimpl_->context
 937                         << ". Got " << token << " instead. Line: " << lineNumber());
 938                 pushToken(token);
 939         }
 940         return *this;
 941 }
 942
 943
 944 bool Lexer::checkFor(char const * required)
 945 {
 946         string token;
 947         *this >> token;
 948         if (token == required)
 949                 return true;
 950         pushToken(token);
 951         return false;
 952 }
 953
 954
 955 void Lexer::setContext(std::string const & str)
 956 {
 957         pimpl_->context = str;
 958 }
 959
 960
 961 } // namespace lyx