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1 /** The math parser
2     \author André Pönitz (2001)
3  */
4
5 /*
6
7 If someone desperately needs partial "structures" (such as a few
8 cells of an array inset or similar) (s)he could uses the
9 following hack as starting point to write some macros:
10
11   \newif\ifcomment
12   \commentfalse
13   \ifcomment
14           \def\makeamptab{\catcode`\&=4\relax}
15           \def\makeampletter{\catcode`\&=11\relax}
16     \def\b{\makeampletter\expandafter\makeamptab\bi}
17     \long\def\bi#1\e{}
18   \else
19     \def\b{}\def\e{}
20   \fi
21
22   ...
23
24   \[\begin{array}{ccc}
25    1 & 2\b & 3^2\\
26    4 & 5\e & 6\\
27    7 & 8 & 9
28   \end{array}\]
29
30 */
31
32
33 #include <config.h>
34
35 #ifdef __GNUG__
36 #pragma implementation
37 #endif
38
39 #include "math_parser.h"
40 #include "math_inset.h"
41 #include "math_arrayinset.h"
42 #include "math_braceinset.h"
43 #include "math_boxinset.h"
44 #include "math_charinset.h"
45 #include "math_deliminset.h"
46 #include "math_envinset.h"
47 #include "math_extern.h"
48 #include "math_factory.h"
49 #include "math_kerninset.h"
50 #include "math_macro.h"
51 #include "math_macrotemplate.h"
52 #include "math_hullinset.h"
53 #include "math_parboxinset.h"
54 #include "math_parinset.h"
55 #include "math_rootinset.h"
56 #include "math_sizeinset.h"
57 #include "math_sqrtinset.h"
58 #include "math_scriptinset.h"
59 #include "math_sqrtinset.h"
60 #include "math_support.h"
61 #include "math_xyarrowinset.h"
62
63 //#include "insets/insetref.h"
64 #include "ref_inset.h"
65
66 #include "lyxlex.h"
67 #include "debug.h"
68 #include "support/LAssert.h"
69 #include "support/lstrings.h"
70
71 #include <cctype>
72 #include <algorithm>
73
74 using std::istream;
75 using std::ostream;
76 using std::ios;
77 using std::endl;
78 using std::fill;
79 using std::vector;
80 using std::atoi;
81
82
83 //#define FILEDEBUG
84
85
86 namespace {
87
88 bool stared(string const & s)
89 {
90         string::size_type const n = s.size();
91         return n && s[n - 1] == '*';
92 }
93
94
95 // These are TeX's catcodes
96 enum CatCode {
97         catEscape,     // 0    backslash
98         catBegin,      // 1    {
99         catEnd,        // 2    }
100         catMath,       // 3    $
101         catAlign,      // 4    &
102         catNewline,    // 5    ^^M
103         catParameter,  // 6    #
104         catSuper,      // 7    ^
105         catSub,        // 8    _
106         catIgnore,     // 9
107         catSpace,      // 10   space
108         catLetter,     // 11   a-zA-Z
109         catOther,      // 12   none of the above
110         catActive,     // 13   ~
111         catComment,    // 14   %
112         catInvalid     // 15   <delete>
113 };
114
115 CatCode theCatcode[256];
116
117
118 inline CatCode catcode(unsigned char c)
119 {
120         return theCatcode[c];
121 }
122
123
124 enum {
125         FLAG_BRACE_LAST = 1 << 1,  //  last closing brace ends the parsing
126         FLAG_RIGHT      = 1 << 2,  //  next \\right ends the parsing process
127         FLAG_END        = 1 << 3,  //  next \\end ends the parsing process
128         FLAG_BRACK_LAST = 1 << 4,  //  next closing bracket ends the parsing
129         FLAG_TEXTMODE   = 1 << 5,  //  we are in a box
130         FLAG_ITEM       = 1 << 6,  //  read a (possibly braced token)
131         FLAG_LEAVE      = 1 << 7,  //  leave the loop at the end
132         FLAG_SIMPLE     = 1 << 8,  //  next $ leaves the loop
133         FLAG_EQUATION   = 1 << 9,  //  next \] leaves the loop
134         FLAG_SIMPLE2    = 1 << 10, //  next \) leaves the loop
135         FLAG_OPTION     = 1 << 11  //  read [...] style option
136 };
137
138
139 void catInit()
140 {
141         fill(theCatcode, theCatcode + 256, catOther);
142         fill(theCatcode + 'a', theCatcode + 'z' + 1, catLetter);
143         fill(theCatcode + 'A', theCatcode + 'Z' + 1, catLetter);
144
145         theCatcode['\\'] = catEscape;
146         theCatcode['{']  = catBegin;
147         theCatcode['}']  = catEnd;
148         theCatcode['$']  = catMath;
149         theCatcode['&']  = catAlign;
150         theCatcode['\n'] = catNewline;
151         theCatcode['#']  = catParameter;
152         theCatcode['^']  = catSuper;
153         theCatcode['_']  = catSub;
154         theCatcode['\7f'] = catIgnore;
155         theCatcode[' ']  = catSpace;
156         theCatcode['\t'] = catSpace;
157         theCatcode['\r'] = catNewline;
158         theCatcode['~']  = catActive;
159         theCatcode['%']  = catComment;
160 }
161
162
163
164 //
165 // Helper class for parsing
166 //
167
168 class Token {
169 public:
170         ///
171         Token() : cs_(), char_(0), cat_(catIgnore) {}
172         ///
173         Token(char c, CatCode cat) : cs_(), char_(c), cat_(cat) {}
174         ///
175         Token(string const & cs) : cs_(cs), char_(0), cat_(catIgnore) {}
176
177         ///
178         string const & cs() const { return cs_; }
179         ///
180         CatCode cat() const { return cat_; }
181         ///
182         char character() const { return char_; }
183         ///
184         string asString() const;
185
186 private:
187         ///
188         string cs_;
189         ///
190         char char_;
191         ///
192         CatCode cat_;
193 };
194
195 string Token::asString() const
196 {
197         return cs_.size() ? cs_ : string(1, char_);
198 }
199
200 ostream & operator<<(ostream & os, Token const & t)
201 {
202         if (t.cs().size())
203                 os << "\\" << t.cs();
204         else
205                 os << "[" << t.character() << "," << t.cat() << "]";
206         return os;
207 }
208
209
210 class Parser {
211
212 public:
213         ///
214         Parser(LyXLex & lex);
215         ///
216         Parser(istream & is);
217
218         ///
219         bool parse(MathAtom & at);
220         ///
221         void parse(MathArray & array, unsigned flags, bool mathmode);
222         ///
223         int lineno() const { return lineno_; }
224         ///
225         void putback();
226
227 private:
228         ///
229         void parse1(MathGridInset & grid, unsigned flags, bool mathmode, bool numbered);
230         ///
231         void parse2(MathAtom & at, unsigned flags, bool mathmode, bool numbered);
232         /// get arg delimited by 'left' and 'right'
233         string getArg(char left, char right);
234         ///
235         char getChar();
236         ///
237         void error(string const & msg);
238         /// dump contents to screen
239         void dump() const;
240         ///
241         void tokenize(istream & is);
242         ///
243         void tokenize(string const & s);
244         ///
245         void skipSpaceTokens(istream & is, char c);
246         ///
247         void push_back(Token const & t);
248         ///
249         void pop_back();
250         ///
251         Token const & prevToken() const;
252         ///
253         Token const & nextToken() const;
254         ///
255         Token const & getToken();
256         /// skips spaces if any
257         void skipSpaces();
258         ///
259         void lex(string const & s);
260         ///
261         bool good() const;
262
263         ///
264         int lineno_;
265         ///
266         vector<Token> tokens_;
267         ///
268         unsigned pos_;
269 };
270
271
272 Parser::Parser(LyXLex & lexer)
273         : lineno_(lexer.getLineNo()), pos_(0)
274 {
275         tokenize(lexer.getStream());
276         lexer.eatLine();
277 }
278
279
280 Parser::Parser(istream & is)
281         : lineno_(0), pos_(0)
282 {
283         tokenize(is);
284 }
285
286
287 void Parser::push_back(Token const & t)
288 {
289         tokens_.push_back(t);
290 }
291
292
293 void Parser::pop_back()
294 {
295         tokens_.pop_back();
296 }
297
298
299 Token const & Parser::prevToken() const
300 {
301         static const Token dummy;
302         return pos_ > 0 ? tokens_[pos_ - 1] : dummy;
303 }
304
305
306 Token const & Parser::nextToken() const
307 {
308         static const Token dummy;
309         return good() ? tokens_[pos_] : dummy;
310 }
311
312
313 Token const & Parser::getToken()
314 {
315         static const Token dummy;
316         //lyxerr << "looking at token " << tokens_[pos_] << " pos: " << pos_ << '\n';
317         return good() ? tokens_[pos_++] : dummy;
318 }
319
320
321 void Parser::skipSpaces()
322 {
323         while (nextToken().cat() == catSpace)
324                 getToken();
325 }
326
327
328 void Parser::putback()
329 {
330         --pos_;
331 }
332
333
334 bool Parser::good() const
335 {
336         return pos_ < tokens_.size();
337 }
338
339
340 char Parser::getChar()
341 {
342         if (!good())
343                 error("The input stream is not well...");
344         return tokens_[pos_++].character();
345 }
346
347
348 string Parser::getArg(char left, char right)
349 {
350         skipSpaces();
351
352         string result;
353         char c = getChar();
354
355         if (c != left)
356                 putback();
357         else
358                 while ((c = getChar()) != right && good())
359                         result += c;
360
361         return result;
362 }
363
364
365 void Parser::skipSpaceTokens(istream & is, char c)
366 {
367         // skip trailing spaces
368         while (catcode(c) == catSpace || catcode(c) == catNewline)
369                 if (!is.get(c))
370                         break;
371         //lyxerr << "putting back: " << c << "\n";
372         is.putback(c);
373 }
374
375
376 void Parser::tokenize(istream & is)
377 {
378         // eat everything up to the next \end_inset or end of stream
379         // and store it in s for further tokenization
380         string s;
381         char c;
382         while (is.get(c)) {
383                 s += c;
384                 if (s.size() >= 10 && s.substr(s.size() - 10) == "\\end_inset") {
385                         s = s.substr(0, s.size() - 10);
386                         break;
387                 }
388         }
389
390         // tokenize buffer
391         tokenize(s);
392 }
393
394
395 void Parser::tokenize(string const & buffer)
396 {
397         static bool init_done = false;
398
399         if (!init_done) {
400                 catInit();
401                 init_done = true;
402         }
403
404         istringstream is(buffer.c_str(), ios::in | ios::binary);
405
406         char c;
407         while (is.get(c)) {
408                 //lyxerr << "reading c: " << c << "\n";
409
410                 switch (catcode(c)) {
411                         case catNewline: {
412                                 ++lineno_;
413                                 is.get(c);
414                                 if (catcode(c) == catNewline)
415                                         ; //push_back(Token("par"));
416                                 else {
417                                         push_back(Token('\n', catNewline));
418                                         is.putback(c);
419                                 }
420                                 break;
421                         }
422
423                         case catComment: {
424                                 while (is.get(c) && catcode(c) != catNewline)
425                                         ;
426                                 ++lineno_;
427                                 break;
428                         }
429
430                         case catEscape: {
431                                 is.get(c);
432                                 if (!is) {
433                                         error("unexpected end of input");
434                                 } else {
435                                         string s(1, c);
436                                         if (catcode(c) == catLetter) {
437                                                 // collect letters
438                                                 while (is.get(c) && catcode(c) == catLetter)
439                                                         s += c;
440                                                 skipSpaceTokens(is, c);
441                                         }
442                                         push_back(Token(s));
443                                 }
444                                 break;
445                         }
446
447                         case catSuper:
448                         case catSub: {
449                                 push_back(Token(c, catcode(c)));
450                                 is.get(c);
451                                 skipSpaceTokens(is, c);
452                                 break;
453                         }
454
455                         case catIgnore: {
456                                 lyxerr << "ignoring a char: " << int(c) << "\n";
457                                 break;
458                         }
459
460                         default:
461                                 push_back(Token(c, catcode(c)));
462                 }
463         }
464
465 #ifdef FILEDEBUG
466         dump();
467 #endif
468 }
469
470
471 void Parser::dump() const
472 {
473         lyxerr << "\nTokens: ";
474         for (unsigned i = 0; i < tokens_.size(); ++i) {
475                 if (i == pos_)
476                         lyxerr << " <#> ";
477                 lyxerr << tokens_[i];
478         }
479         lyxerr << " pos: " << pos_ << "\n";
480 }
481
482
483 void Parser::error(string const & msg)
484 {
485         lyxerr << "Line ~" << lineno_ << ": Math parse error: " << msg << endl;
486         dump();
487         //exit(1);
488 }
489
490
491 bool Parser::parse(MathAtom & at)
492 {
493         skipSpaces();
494         MathArray ar;
495         parse(ar, false, false);
496         if (ar.size() != 1 || ar.front()->getType() == "none") {
497                 lyxerr << "unusual contents found: " << ar << endl;
498                 at.reset(new MathParInset);
499                 if (at->nargs() > 0)
500                         at->cell(0) = ar;
501                 else
502                         lyxerr << "unusual contents found: " << ar << endl;
503                 return true;
504         }
505         at = ar[0];
506         return true;
507 }
508
509
510 void Parser::parse(MathArray & array, unsigned flags, bool mathmode)
511 {
512         MathGridInset grid(1, 1);
513         parse1(grid, flags, mathmode, false);
514         array = grid.cell(0);
515 }
516
517
518 void Parser::parse2(MathAtom & at, unsigned flags,
519         bool mathmode, bool numbered)
520 {
521         parse1(*(at->asGridInset()), flags, mathmode, numbered);
522 }
523
524
525 void Parser::parse1(MathGridInset & grid, unsigned flags,
526         bool mathmode, bool numbered)
527 {
528         int  limits = 0;
529         MathGridInset::row_type cellrow = 0;
530         MathGridInset::col_type cellcol = 0;
531         MathArray * cell = &grid.cell(grid.index(cellrow, cellcol));
532
533         if (grid.asHullInset())
534                 grid.asHullInset()->numbered(cellrow, numbered);
535
536         //dump();
537         //lyxerr << "grid: " << grid << endl;
538
539         while (good()) {
540                 Token const & t = getToken();
541
542 #ifdef FILEDEBUG
543                 lyxerr << "t: " << t << " flags: " << flags << "\n";
544                 //cell->dump();
545                 lyxerr << "\n";
546 #endif
547
548                 if (flags & FLAG_ITEM) {
549                         if (t.cat() == catSpace)
550                                 continue;
551
552                         flags &= ~FLAG_ITEM;
553                         if (t.cat() == catBegin) {
554                                 // skip the brace and collect everything to the next matching
555                                 // closing brace
556                                 flags |= FLAG_BRACE_LAST;
557                                 continue;
558                         }
559
560                         // handle only this single token, leave the loop if done
561                         flags |= FLAG_LEAVE;
562                 }
563
564
565                 if (flags & FLAG_OPTION) {
566                         if (t.cat() == catOther && t.character() == '[') {
567                                 // skip the bracket and collect everything to the closing bracket
568                                 flags |= FLAG_BRACK_LAST;
569                                 continue;
570                         }
571
572                         // no option found, put back token and we are done
573                         putback();
574                         return;
575                 }
576
577                 //
578                 // cat codes
579                 //
580                 if (t.cat() == catMath) {
581                         if (!mathmode) {
582                                 // we are inside some text mode thingy, so opening new math is allowed
583                                 Token const & n = getToken();
584                                 if (n.cat() == catMath) {
585                                         // TeX's $$...$$ syntax for displayed math
586                                         cell->push_back(MathAtom(new MathHullInset("equation")));
587                                         parse2(cell->back(), FLAG_SIMPLE, true, false);
588                                         getToken(); // skip the second '$' token
589                                 } else {
590                                         // simple $...$  stuff
591                                         putback();
592                                         cell->push_back(MathAtom(new MathHullInset("simple")));
593                                         parse2(cell->back(), FLAG_SIMPLE, true, false);
594                                 }
595                         }
596
597                         else if (flags & FLAG_SIMPLE) {
598                                 // this is the end of the formula
599                                 return;
600                         }
601
602                         else {
603                                 error("something strange in the parser\n");
604                                 break;
605                         }
606                 }
607
608                 else if (t.cat() == catLetter)
609                         cell->push_back(MathAtom(new MathCharInset(t.character())));
610
611                 else if (t.cat() == catSpace && !mathmode)
612                         cell->push_back(MathAtom(new MathCharInset(t.character())));
613
614                 else if (t.cat() == catNewline && !mathmode)
615                         cell->push_back(MathAtom(new MathCharInset(t.character())));
616
617                 else if (t.cat() == catParameter) {
618                         Token const & n = getToken();
619                         cell->push_back(MathAtom(new MathMacroArgument(n.character()-'0')));
620                 }
621
622                 else if (t.cat() == catBegin) {
623                         MathArray ar;
624                         parse(ar, FLAG_BRACE_LAST, mathmode);
625                         // do not create a BraceInset if they were written by LyX
626                         // this helps to keep the annoyance of  "a choose b"  to a minimum
627                         if (ar.size() == 1 && ar[0]->extraBraces())
628                                 cell->append(ar);
629                         else
630                                 cell->push_back(MathAtom(new MathBraceInset(ar)));
631                 }
632
633                 else if (t.cat() == catEnd) {
634                         if (flags & FLAG_BRACE_LAST)
635                                 return;
636                         error("found '}' unexpectedly");
637                         //lyx::Assert(0);
638                         //add(cell, '}', LM_TC_TEX);
639                 }
640
641                 else if (t.cat() == catAlign) {
642                         ++cellcol;
643                         //lyxerr << " column now " << cellcol << " max: " << grid.ncols() << "\n";
644                         if (cellcol == grid.ncols()) {
645                                 lyxerr << "adding column " << cellcol << "\n";
646                                 grid.addCol(cellcol - 1);
647                         }
648                         cell = &grid.cell(grid.index(cellrow, cellcol));
649                 }
650
651                 else if (t.cat() == catSuper || t.cat() == catSub) {
652                         bool up = (t.cat() == catSuper);
653                         // we need no new script inset if the last thing was a scriptinset,
654                         // which has that script already not the same script already
655                         if (cell->size() && cell->back()->asScriptInset() &&
656                             !cell->back()->asScriptInset()->has(up))
657                                 cell->back()->asScriptInset()->ensure(up);
658                         else if (cell->back()->asScriptInset())
659                                 cell->push_back(MathAtom(new MathScriptInset(up)));
660                         else
661                                 cell->back() = MathAtom(new MathScriptInset(cell->back(), up));
662                         MathScriptInset * p = cell->back()->asScriptInset();
663                         parse(p->cell(up), FLAG_ITEM, mathmode);
664                         p->limits(limits);
665                         limits = 0;
666                 }
667
668                 else if (t.character() == ']' && (flags & FLAG_BRACK_LAST))
669                         return;
670
671                 else if (t.cat() == catOther)
672                         cell->push_back(MathAtom(new MathCharInset(t.character())));
673
674                 //
675                 // control sequences
676                 //
677
678                 else if (t.cs() == "def" || t.cs() == "newcommand") {
679                         string name;
680                         int nargs = 0;
681                         if (t.cs() == "def") {
682                                 // get name
683                                 name = getToken().cs();
684
685                                 // read parameter
686                                 string pars;
687                                 while (good() && nextToken().cat() != catBegin) {
688                                         pars += getToken().cs();
689                                         ++nargs;
690                                 }
691                                 nargs /= 2;
692                                 //lyxerr << "read \\def parameter list '" << pars << "'\n";
693
694                         } else { // t.cs() == "newcommand"
695
696                                 if (getToken().cat() != catBegin) {
697                                         error("'{' in \\newcommand expected (1) \n");
698                                         return;
699                                 }
700
701                                 name = getToken().cs();
702
703                                 if (getToken().cat() != catEnd) {
704                                         error("'}' in \\newcommand expected\n");
705                                         return;
706                                 }
707
708                                 string arg  = getArg('[', ']');
709                                 if (!arg.empty())
710                                         nargs = atoi(arg.c_str());
711
712                         }
713
714                         MathArray ar1;
715                         parse(ar1, FLAG_ITEM, true);
716
717                         // we cannot handle recursive stuff at all
718                         //MathArray test;
719                         //test.push_back(createMathInset(name));
720                         //if (ar1.contains(test)) {
721                         //      error("we cannot handle recursive macros at all.\n");
722                         //      return;
723                         //}
724
725                         // is a version for display attached?
726                         skipSpaces();
727                         MathArray ar2;
728                         if (nextToken().cat() == catBegin) {
729                                 parse(ar2, FLAG_ITEM, true);
730                         }
731
732                         cell->push_back(MathAtom(new MathMacroTemplate(name, nargs, ar1, ar2)));
733                 }
734
735                 else if (t.cs() == "(") {
736                         cell->push_back(MathAtom(new MathHullInset("simple")));
737                         parse2(cell->back(), FLAG_SIMPLE2, true, false);
738                 }
739
740                 else if (t.cs() == "[") {
741                         cell->push_back(MathAtom(new MathHullInset("equation")));
742                         parse2(cell->back(), FLAG_EQUATION, true, false);
743                 }
744
745                 else if (t.cs() == "protect")
746                         // ignore \\protect, will hopefully be re-added during output
747                         ;
748
749                 else if (t.cs() == "end") {
750                         if (flags & FLAG_END) {
751                                 // eat environment name
752                                 //string const name =
753                                 getArg('{', '}');
754                                 // FIXME: check that we ended the correct environment
755                                 return;
756                         }
757                         error("found 'end' unexpectedly");
758                 }
759
760                 else if (t.cs() == ")") {
761                         if (flags & FLAG_SIMPLE2)
762                                 return;
763                         error("found '\\)' unexpectedly");
764                 }
765
766                 else if (t.cs() == "]") {
767                         if (flags & FLAG_EQUATION)
768                                 return;
769                         error("found '\\]' unexpectedly");
770                 }
771
772                 else if (t.cs() == "\\") {
773                         grid.vcrskip(LyXLength(getArg('[', ']')), cellrow);
774                         ++cellrow;
775                         cellcol = 0;
776                         if (cellrow == grid.nrows())
777                                 grid.addRow(cellrow - 1);
778                         if (grid.asHullInset())
779                                 grid.asHullInset()->numbered(cellrow, numbered);
780                         cell = &grid.cell(grid.index(cellrow, cellcol));
781                 }
782
783 #if 1
784                 else if (t.cs() == "multicolumn") {
785                         // extract column count and insert dummy cells
786                         MathArray count;
787                         parse(count, FLAG_ITEM, mathmode);
788                         int cols = 1;
789                         if (!extractNumber(count, cols)) {
790                                 lyxerr << " can't extract number of cells from " << count << "\n";
791                         }
792                         // resize the table if necessary
793                         for (int i = 0; i < cols; ++i) {
794                                 ++cellcol;
795                                 if (cellcol == grid.ncols()) {
796                                         lyxerr << "adding column " << cellcol << "\n";
797                                         grid.addCol(cellcol - 1);
798                                 }
799                                 cell = &grid.cell(grid.index(cellrow, cellcol));
800                                 // mark this as dummy
801                                 grid.cellinfo(grid.index(cellrow, cellcol)).dummy_ = true;
802                         }
803                         // the last cell is the real thng, not a dummy
804                         grid.cellinfo(grid.index(cellrow, cellcol)).dummy_ = false;
805
806                         // read special alignment
807                         MathArray align;
808                         parse(align, FLAG_ITEM, mathmode);
809                         //grid.cellinfo(grid.index(cellrow, cellcol)).align_ = extractString(align);
810
811                         // parse the remaining contents into the "real" cell
812                         parse(*cell, FLAG_ITEM, mathmode);
813                 }
814 #endif
815
816                 else if (t.cs() == "limits")
817                         limits = 1;
818
819                 else if (t.cs() == "nolimits")
820                         limits = -1;
821
822                 else if (t.cs() == "nonumber") {
823                         if (grid.asHullInset())
824                                 grid.asHullInset()->numbered(cellrow, false);
825                 }
826
827                 else if (t.cs() == "number") {
828                         if (grid.asHullInset())
829                                 grid.asHullInset()->numbered(cellrow, true);
830                 }
831
832                 else if (t.cs() == "hline") {
833                         if (grid.asHullInset())
834                                 grid.asHullInset()->rowinfo(cellrow + 1);
835                 }
836
837                 else if (t.cs() == "sqrt") {
838                         MathArray ar;
839                         parse(ar, FLAG_OPTION, mathmode);
840                         if (ar.size()) {
841                                 cell->push_back(MathAtom(new MathRootInset));
842                                 cell->back()->cell(0) = ar;
843                                 parse(cell->back()->cell(1), FLAG_ITEM, mathmode);
844                         } else {
845                                 cell->push_back(MathAtom(new MathSqrtInset));
846                                 parse(cell->back()->cell(0), FLAG_ITEM, mathmode);
847                         }
848                 }
849
850                 else if (t.cs() == "ref") {
851                         cell->push_back(MathAtom(new RefInset));
852                         parse(cell->back()->cell(1), FLAG_OPTION, mathmode);
853                         parse(cell->back()->cell(0), FLAG_ITEM, mathmode);
854                 }
855
856                 else if (t.cs() == "left") {
857                         string l = getToken().asString();
858                         MathArray ar;
859                         parse(ar, FLAG_RIGHT, mathmode);
860                         string r = getToken().asString();
861                         cell->push_back(MathAtom(new MathDelimInset(l, r, ar)));
862                 }
863
864                 else if (t.cs() == "right") {
865                         if (flags & FLAG_RIGHT)
866                                 return;
867                         //lyxerr << "got so far: '" << cell << "'\n";
868                         error("Unmatched right delimiter");
869                         return;
870                 }
871
872                 else if (t.cs() == "begin") {
873                         string const name = getArg('{', '}');
874                         if (name == "array" || name == "subarray") {
875                                 string const valign = getArg('[', ']') + 'c';
876                                 string const halign = getArg('{', '}');
877                                 cell->push_back(MathAtom(new MathArrayInset(name, valign[0], halign)));
878                                 parse2(cell->back(), FLAG_END, mathmode, false);
879                         }
880
881                         else if (name == "split" || name == "cases" ||
882                                          name == "gathered" || name == "aligned") {
883                                 cell->push_back(createMathInset(name));
884                                 parse2(cell->back(), FLAG_END, mathmode, false);
885                         }
886
887                         else if (name == "math") {
888                                 cell->push_back(MathAtom(new MathHullInset("simple")));
889                                 parse2(cell->back(), FLAG_END, true, true);
890                         }
891
892                         else if (name == "equation" || name == "equation*"
893                                         || name == "displaymath") {
894                                 cell->push_back(MathAtom(new MathHullInset("equation")));
895                                 parse2(cell->back(), FLAG_END, true, (name == "equation"));
896                         }
897
898                         else if (name == "eqnarray" || name == "eqnarray*") {
899                                 cell->push_back(MathAtom(new MathHullInset("eqnarray")));
900                                 parse2(cell->back(), FLAG_END, true, !stared(name));
901                         }
902
903                         else if (name == "align" || name == "align*") {
904                                 cell->push_back(MathAtom(new MathHullInset("align")));
905                                 parse2(cell->back(), FLAG_END, true, !stared(name));
906                         }
907
908                         else if (name == "alignat" || name == "alignat*") {
909                                 // ignore this for a while
910                                 getArg('{', '}');
911                                 cell->push_back(MathAtom(new MathHullInset("alignat")));
912                                 parse2(cell->back(), FLAG_END, true, !stared(name));
913                         }
914
915                         else if (name == "xalignat" || name == "xalignat*") {
916                                 // ignore this for a while
917                                 getArg('{', '}');
918                                 cell->push_back(MathAtom(new MathHullInset("xalignat")));
919                                 parse2(cell->back(), FLAG_END, true, !stared(name));
920                         }
921
922                         else if (name == "xxalignat") {
923                                 // ignore this for a while
924                                 getArg('{', '}');
925                                 cell->push_back(MathAtom(new MathHullInset("xxalignat")));
926                                 parse2(cell->back(), FLAG_END, true, !stared(name));
927                         }
928
929                         else if (name == "multline" || name == "multline*") {
930                                 cell->push_back(MathAtom(new MathHullInset("multline")));
931                                 parse2(cell->back(), FLAG_END, true, !stared(name));
932                         }
933
934                         else if (name == "gather" || name == "gather*") {
935                                 cell->push_back(MathAtom(new MathHullInset("gather")));
936                                 parse2(cell->back(), FLAG_END, true, !stared(name));
937                         }
938
939                         else if (latexkeys const * l = in_word_set(name)) {
940                                 if (l->inset == "matrix") {
941                                         cell->push_back(createMathInset(name));
942                                         parse2(cell->back(), FLAG_END, mathmode, false);
943                                 }
944                         }
945
946                         else {
947                                 // lyxerr << "unknow math inset begin '" << name << "'\n";
948                                 // create generic environment inset
949                                 cell->push_back(MathAtom(new MathEnvInset(name)));
950                                 parse(cell->back()->cell(0), FLAG_END, mathmode);
951                         }
952                 }
953
954                 else if (t.cs() == "kern") {
955 #ifdef WITH_WARNINGS
956 #warning A hack...
957 #endif
958                         string s;
959                         while (1) {
960                                 Token const & t = getToken();
961                                 if (!good()) {
962                                         putback();
963                                         break;
964                                 }
965                                 s += t.character();
966                                 if (isValidLength(s))
967                                         break;
968                         }
969                         cell->push_back(MathAtom(new MathKernInset(s)));
970                 }
971
972                 else if (t.cs() == "label") {
973                         MathArray ar;
974                         parse(ar, FLAG_ITEM, false);
975                         if (grid.asHullInset()) {
976                                 grid.asHullInset()->label(cellrow, asString(ar));
977                         } else {
978                                 cell->push_back(createMathInset(t.cs()));
979                                 cell->push_back(MathAtom(new MathBraceInset(ar)));
980                         }
981                 }
982
983                 else if (t.cs() == "choose" || t.cs() == "over" || t.cs() == "atop") {
984                         MathAtom p = createMathInset(t.cs());
985                         p->cell(0) = *cell;
986                         cell->clear();
987                         parse(p->cell(1), flags, mathmode);
988                         cell->push_back(p);
989                         return;
990                 }
991
992                 else if (t.cs() == "substack") {
993                         cell->push_back(createMathInset(t.cs()));
994                         parse2(cell->back(), FLAG_ITEM, mathmode, false);
995                 }
996
997                 else if (t.cs() == "xymatrix") {
998                         cell->push_back(createMathInset(t.cs()));
999                         parse2(cell->back(), FLAG_ITEM, mathmode, false);
1000                 }
1001
1002 #if 0
1003                 // Disabled
1004                 else if (1 && t.cs() == "ar") {
1005                         MathXYArrowInset * p = new MathXYArrowInset;
1006                         // try to read target
1007                         parse(p->cell(0), FLAG_OTPTION, mathmode);
1008                         // try to read label
1009                         if (nextToken().cat() == catSuper || nextToken().cat() == catSub) {
1010                                 p->up_ = nextToken().cat() == catSuper;
1011                                 getToken();
1012                                 parse(p->cell(1), FLAG_ITEM, mathmode);
1013                                 //lyxerr << "read label: " << p->cell(1) << "\n";
1014                         }
1015
1016                         cell->push_back(MathAtom(p));
1017                         //lyxerr << "read cell: " << cell << "\n";
1018                 }
1019 #endif
1020
1021                 else if (t.cs().size()) {
1022                         latexkeys const * l = in_word_set(t.cs());
1023                         if (l) {
1024                                 if (l->inset == "font") {
1025                                         cell->push_back(createMathInset(t.cs()));
1026                                         parse(cell->back()->cell(0), FLAG_ITEM, l->extra == "mathmode");
1027                                 }
1028
1029                                 else if (l->inset == "oldfont") {
1030                                         cell->push_back(createMathInset(t.cs()));
1031                                         parse(cell->back()->cell(0), flags, l->extra == "mathmode");
1032                                         return;
1033                                 }
1034
1035                                 else if (l->inset == "style") {
1036                                         cell->push_back(createMathInset(t.cs()));
1037                                         parse(cell->back()->cell(0), flags, mathmode);
1038                                         return;
1039                                 }
1040
1041                                 else if (l->inset == "parbox") {
1042                                         // read optional positioning and width
1043                                         MathArray pos, width;
1044                                         parse(pos, FLAG_OPTION, false);
1045                                         parse(width, FLAG_ITEM, false);
1046                                         cell->push_back(createMathInset(t.cs()));
1047                                         parse(cell->back()->cell(0), FLAG_ITEM, false);
1048                                         cell->back()->asParboxInset()->setPosition(asString(pos));
1049                                         cell->back()->asParboxInset()->setWidth(asString(width));
1050                                 }
1051
1052                                 else {
1053                                         MathAtom p = createMathInset(t.cs());
1054                                         for (MathInset::idx_type i = 0; i < p->nargs(); ++i)
1055                                                 parse(p->cell(i), FLAG_ITEM, l->extra != "forcetext");
1056                                         cell->push_back(p);
1057                                 }
1058                         }
1059
1060                         else {
1061                                 MathAtom p = createMathInset(t.cs());
1062                                 bool mode = mathmode;
1063                                 if (mathmode && p->currentMode() == MathInset::TEXT_MODE)
1064                                         mode = false;
1065                                 if (!mathmode && p->currentMode() == MathInset::MATH_MODE)
1066                                         mode = true;
1067                                 for (MathInset::idx_type i = 0; i < p->nargs(); ++i)
1068                                         parse(p->cell(i), FLAG_ITEM, mode);
1069                                 cell->push_back(p);
1070                         }
1071                 }
1072
1073
1074                 if (flags & FLAG_LEAVE) {
1075                         flags &= ~FLAG_LEAVE;
1076                         break;
1077                 }
1078         }
1079 }
1080
1081
1082
1083 } // anonymous namespace
1084
1085
1086 void mathed_parse_cell(MathArray & ar, string const & str)
1087 {
1088         istringstream is(str.c_str());
1089         mathed_parse_cell(ar, is);
1090 }
1091
1092
1093 void mathed_parse_cell(MathArray & ar, istream & is)
1094 {
1095         Parser(is).parse(ar, 0, true);
1096 }
1097
1098
1099 bool mathed_parse_normal(MathAtom & t, string const & str)
1100 {
1101         istringstream is(str.c_str());
1102         return Parser(is).parse(t);
1103 }
1104
1105
1106 bool mathed_parse_normal(MathAtom & t, istream & is)
1107 {
1108         return Parser(is).parse(t);
1109 }
1110
1111
1112 bool mathed_parse_normal(MathAtom & t, LyXLex & lex)
1113 {
1114         return Parser(lex).parse(t);
1115 }