src/mathed/MathFactory.cpp

   1 /**
   2  * \file MathFactory.cpp
   3  * This file is part of LyX, the document processor.
   4  * Licence details can be found in the file COPYING.
   5  *
   6  * \author André Pönitz
   7  *
   8  * Full author contact details are available in file CREDITS.
   9  */
  10
  11 #include <config.h>
  12
  13 #include "MathFactory.h"
  14
  15 #include "InsetMathAMSArray.h"
  16 #include "InsetMathArray.h"
  17 #include "InsetMathBoldSymbol.h"
  18 #include "InsetMathBox.h"
  19 #include "InsetMathCancel.h"
  20 #include "InsetMathCancelto.h"
  21 #include "InsetMathCases.h"
  22 #include "InsetMathColor.h"
  23 #include "InsetMathDecoration.h"
  24 #include "InsetMathDots.h"
  25 #include "InsetMathEnsureMath.h"
  26 #include "InsetMathFont.h"
  27 #include "InsetMathFontOld.h"
  28 #include "InsetMathFrac.h"
  29 #include "InsetMathKern.h"
  30 #include "InsetMathLefteqn.h"
  31 #include "InsetMathOverset.h"
  32 #include "InsetMathPhantom.h"
  33 #include "InsetMathRef.h"
  34 #include "InsetMathRoot.h"
  35 #include "InsetMathSize.h"
  36 #include "InsetMathSpace.h"
  37 #include "InsetMathSpecialChar.h"
  38 #include "InsetMathSplit.h"
  39 #include "InsetMathSqrt.h"
  40 #include "InsetMathStackrel.h"
  41 #include "InsetMathSubstack.h"
  42 #include "InsetMathSymbol.h"
  43 #include "InsetMathTabular.h"
  44 #include "InsetMathUnderset.h"
  45 #include "InsetMathUnknown.h"
  46 #include "InsetMathHull.h"
  47 #include "InsetMathXArrow.h"
  48 #include "InsetMathXYMatrix.h"
  49 #include "InsetMathDiagram.h"
  50 #include "MacroTable.h"
  51 #include "MathMacro.h"
  52 #include "MathMacroArgument.h"
  53 #include "MathParser.h"
  54 #include "MathStream.h"
  55 #include "MathSupport.h"
  56
  57 #include "insets/InsetCommand.h"
  58 #include "insets/InsetSpace.h"
  59
  60 #include "support/debug.h"
  61 #include "support/docstream.h"
  62 #include "support/FileName.h"
  63 #include "support/filetools.h" // LibFileSearch
  64 #include "support/lstrings.h"
  65
  66 #include "frontends/FontLoader.h"
  67
  68 #include "Buffer.h"
  69 #include "BufferParams.h"
  70 #include "Encoding.h"
  71 #include "LyX.h" // use_gui
  72 #include "OutputParams.h"
  73
  74 using namespace std;
  75 using namespace lyx::support;
  76
  77 namespace lyx {
  78
  79 bool has_math_fonts;
  80
  81
  82 namespace {
  83
  84 MathWordList theMathWordList;
  85
  86
  87 bool isMathFontAvailable(docstring & name)
  88 {
  89         if (!use_gui)
  90                 return false;
  91
  92         FontInfo f;
  93         augmentFont(f, name);
  94
  95         // Do we have the font proper?
  96         if (theFontLoader().available(f))
  97                 return true;
  98
  99         // can we fake it?
 100         if (name == "eufrak") {
 101                 name = from_ascii("lyxfakefrak");
 102                 return true;
 103         }
 104
 105         LYXERR(Debug::MATHED,
 106                 "font " << to_utf8(name) << " not available and I can't fake it");
 107         return false;
 108 }
 109
 110
 111 void initSymbols()
 112 {
 113         FileName const filename = libFileSearch(string(), "symbols");
 114         LYXERR(Debug::MATHED, "read symbols from " << filename);
 115         if (filename.empty()) {
 116                 lyxerr << "Could not find symbols file" << endl;
 117                 return;
 118         }
 119
 120         ifstream fs(filename.toFilesystemEncoding().c_str());
 121         string line;
 122         bool skip = false;
 123         while (getline(fs, line)) {
 124                 int charid     = 0;
 125                 int fallbackid = 0;
 126                 if (line.empty() || line[0] == '#')
 127                         continue;
 128
 129                 // special case of iffont/else/endif
 130                 if (line.size() >= 7 && line.substr(0, 6) == "iffont") {
 131                         istringstream is(line);
 132                         string tmp;
 133                         is >> tmp;
 134                         is >> tmp;
 135                         docstring t = from_utf8(tmp);
 136                         skip = !isMathFontAvailable(t);
 137                         continue;
 138                 } else if (line.size() >= 4 && line.substr(0, 4) == "else") {
 139                         skip = !skip;
 140                         continue;
 141                 } else if (line.size() >= 5 && line.substr(0, 5) == "endif") {
 142                         skip = false;
 143                         continue;
 144                 } else if (skip)
 145                         continue;
 146
 147                 // special case of pre-defined macros
 148                 if (line.size() > 8 && line.substr(0, 5) == "\\def\\") {
 149                         //lyxerr << "macro definition: '" << line << '\'' << endl;
 150                         istringstream is(line);
 151                         string macro;
 152                         string requires;
 153                         is >> macro >> requires;
 154                         MacroTable::iterator it = MacroTable::globalMacros().insert(
 155                                         0, from_utf8(macro), requires);
 156                         // If you change the following output, please adjust
 157                         // development/tools/generate_symbols_images.py.
 158                         LYXERR(Debug::MATHED, "read symbol '" << to_utf8(it->first)
 159                                 << "  inset: macro"
 160                                 << "  draw: 0"
 161                                 << "  extra: "
 162                                 << "  requires: " << requires << '\'');
 163                         continue;
 164                 }
 165
 166                 idocstringstream is(from_utf8(line));
 167                 latexkeys tmp;
 168                 is >> tmp.name >> tmp.inset;
 169                 if (isFontName(tmp.inset))
 170                         is >> charid >> fallbackid >> tmp.extra >> tmp.xmlname;
 171                 else
 172                         is >> tmp.extra;
 173                 // requires is optional
 174                 if (is) {
 175                         is >> tmp.requires;
 176                         // backward compatibility
 177                         if (tmp.requires == "esintoramsmath")
 178                                 tmp.requires = from_ascii("esint|amsmath");
 179                 } else {
 180                         LYXERR(Debug::MATHED, "skipping line '" << line << "'\n"
 181                                 << to_utf8(tmp.name) << ' ' << to_utf8(tmp.inset) << ' '
 182                                 << to_utf8(tmp.extra));
 183                         continue;
 184                 }
 185
 186                 if (isFontName(tmp.inset)) {
 187                         // tmp.inset _is_ the fontname here.
 188                         // create fallbacks if necessary
 189
 190                         // store requirements as long as we can
 191                         if (tmp.requires.empty()) {
 192                                 if (tmp.inset == "msa" || tmp.inset == "msb")
 193                                         tmp.requires = from_ascii("amssymb");
 194                                 else if (tmp.inset == "wasy")
 195                                         tmp.requires = from_ascii("wasysym");
 196                                 else if (tmp.inset == "mathscr")
 197                                         tmp.requires = from_ascii("mathrsfs");
 198                         }
 199
 200                         // symbol font is not available sometimes
 201                         docstring symbol_font = from_ascii("lyxsymbol");
 202
 203                         if (tmp.extra == "func" || tmp.extra == "funclim" || tmp.extra == "special") {
 204                                 LYXERR(Debug::MATHED, "symbol abuse for " << to_utf8(tmp.name));
 205                                 tmp.draw = tmp.name;
 206                         } else if (isMathFontAvailable(tmp.inset)) {
 207                                 LYXERR(Debug::MATHED, "symbol available for " << to_utf8(tmp.name));
 208                                 tmp.draw.push_back(char_type(charid));
 209                         } else if (fallbackid && isMathFontAvailable(symbol_font)) {
 210                                 if (tmp.inset == "cmex")
 211                                         tmp.inset = from_ascii("lyxsymbol");
 212                                 else
 213                                         tmp.inset = from_ascii("lyxboldsymbol");
 214                                 LYXERR(Debug::MATHED, "symbol fallback for " << to_utf8(tmp.name));
 215                                 tmp.draw.push_back(char_type(fallbackid));
 216                         } else {
 217                                 LYXERR(Debug::MATHED, "faking " << to_utf8(tmp.name));
 218                                 tmp.draw = tmp.name;
 219                                 tmp.inset = from_ascii("lyxtex");
 220                         }
 221                 } else {
 222                         // it's a proper inset
 223                         LYXERR(Debug::MATHED, "inset " << to_utf8(tmp.inset)
 224                                               << " used for " << to_utf8(tmp.name));
 225                 }
 226
 227                 if (theMathWordList.find(tmp.name) != theMathWordList.end())
 228                         LYXERR(Debug::MATHED, "readSymbols: inset " << to_utf8(tmp.name)
 229                                 << " already exists.");
 230                 else
 231                         theMathWordList[tmp.name] = tmp;
 232
 233                 // If you change the following output, please adjust
 234                 // development/tools/generate_symbols_images.py.
 235                 LYXERR(Debug::MATHED, "read symbol '" << to_utf8(tmp.name)
 236                         << "  inset: " << to_utf8(tmp.inset)
 237                         << "  draw: " << int(tmp.draw.empty() ? 0 : tmp.draw[0])
 238                         << "  extra: " << to_utf8(tmp.extra)
 239                         << "  requires: " << to_utf8(tmp.requires) << '\'');
 240         }
 241         docstring tmp = from_ascii("cmm");
 242         docstring tmp2 = from_ascii("cmsy");
 243         has_math_fonts = isMathFontAvailable(tmp) && isMathFontAvailable(tmp2);
 244 }
 245
 246
 247 bool isSpecialChar(docstring const & name)
 248 {
 249         if (name.size() != 1)
 250                 return  name == "textasciicircum" || name == "mathcircumflex" ||
 251                         name == "textasciitilde"  || name == "textbackslash";
 252
 253         char_type const c = name.at(0);
 254         return  c == '{' || c == '}' || c == '&' || c == '$' ||
 255                 c == '#' || c == '%' || c == '_';
 256 }
 257
 258
 259 } // namespace anon
 260
 261 MathWordList const & mathedWordList()
 262 {
 263         return theMathWordList;
 264 }
 265
 266
 267 void initMath()
 268 {
 269         static bool initialized = false;
 270         if (!initialized) {
 271                 initialized = true;
 272                 initParser();
 273                 initSymbols();
 274         }
 275 }
 276
 277
 278 bool ensureMath(WriteStream & os, bool needs_math_mode, bool macro)
 279 {
 280         bool brace = os.pendingBrace();
 281         os.pendingBrace(false);
 282         if (!os.latex())
 283                 return brace;
 284         if (os.textMode() && needs_math_mode) {
 285                 os << "\\ensuremath{";
 286                 os.textMode(false);
 287                 brace = true;
 288         } else if (macro && brace && !needs_math_mode) {
 289                 // This is a user defined macro, but not a MathMacro, so we
 290                 // cannot be sure what mode is needed. As it was entered in
 291                 // a text box, we restore the text mode.
 292                 os << '}';
 293                 os.textMode(true);
 294                 brace = false;
 295         }
 296         return brace;
 297 }
 298
 299
 300 int ensureMode(WriteStream & os, InsetMath::mode_type mode,
 301                 bool locked, bool ascii)
 302 {
 303         bool textmode = mode == InsetMath::TEXT_MODE;
 304         if (os.latex() && textmode && os.pendingBrace()) {
 305                 os.os() << '}';
 306                 os.pendingBrace(false);
 307                 os.pendingSpace(false);
 308                 os.textMode(true);
 309         }
 310         int oldmodes = os.textMode() ? 0x01 : 0;
 311         os.textMode(textmode);
 312         oldmodes |= os.lockedMode() ? 0x02 : 0;
 313         os.lockedMode(locked);
 314         oldmodes |= os.asciiOnly() ? 0x04 : 0;
 315         os.asciiOnly(ascii);
 316         return oldmodes;
 317 }
 318
 319
 320 latexkeys const * in_word_set(docstring const & str)
 321 {
 322         MathWordList::iterator it = theMathWordList.find(str);
 323         return it != theMathWordList.end() ? &(it->second) : 0;
 324 }
 325
 326
 327 MathAtom createInsetMath(char const * const s, Buffer * buf)
 328 {
 329         return createInsetMath(from_utf8(s), buf);
 330 }
 331
 332
 333 MathAtom createInsetMath(docstring const & s, Buffer * buf)
 334 {
 335         //lyxerr << "creating inset with name: '" << to_utf8(s) << '\'' << endl;
 336         if ((s == "ce" || s == "cf") && buf
 337             && buf->params().use_package("mhchem") == BufferParams::package_off)
 338                 return MathAtom(new MathMacro(buf, s));
 339
 340         latexkeys const * l = in_word_set(s);
 341         if (l) {
 342                 docstring const & inset = l->inset;
 343                 //lyxerr << " found inset: '" << inset << '\'' << endl;
 344                 if (inset == "ref")
 345                         return MathAtom(new InsetMathRef(buf, l->name));
 346                 if (inset == "overset")
 347                         return MathAtom(new InsetMathOverset(buf));
 348                 if (inset == "underset")
 349                         return MathAtom(new InsetMathUnderset(buf));
 350                 if (inset == "decoration")
 351                         return MathAtom(new InsetMathDecoration(buf, l));
 352                 if (inset == "space")
 353                         return MathAtom(new InsetMathSpace(to_ascii(l->name), ""));
 354                 if (inset == "dots")
 355                         return MathAtom(new InsetMathDots(l));
 356                 if (inset == "mbox")
 357                         // return MathAtom(new InsetMathMBox);
 358                         // InsetMathMBox is proposed to replace InsetMathBox,
 359                         // but is not ready yet (it needs a BufferView for
 360                         // construction)
 361                         return MathAtom(new InsetMathBox(buf, l->name));
 362 //              if (inset == "fbox")
 363 //                      return MathAtom(new InsetMathFBox(l));
 364                 if (inset == "style")
 365                         return MathAtom(new InsetMathSize(buf, l));
 366                 if (inset == "font")
 367                         return MathAtom(new InsetMathFont(buf, l));
 368                 if (inset == "oldfont")
 369                         return MathAtom(new InsetMathFontOld(buf, l));
 370                 if (inset == "matrix")
 371                         return MathAtom(new InsetMathAMSArray(buf, s));
 372                 if (inset == "split")
 373                         return MathAtom(new InsetMathSplit(buf, s));
 374                 if (inset == "big")
 375                         // we can't create a InsetMathBig, since the argument
 376                         // is missing.
 377                         return MathAtom(new InsetMathUnknown(s));
 378                 return MathAtom(new InsetMathSymbol(l));
 379         }
 380
 381         if (s.size() == 2 && s[0] == '#' && s[1] >= '1' && s[1] <= '9')
 382                 return MathAtom(new MathMacroArgument(s[1] - '0'));
 383         if (s.size() == 3 && s[0] == '\\' && s[1] == '#'
 384                         && s[2] >= '1' && s[2] <= '9')
 385                 return MathAtom(new MathMacroArgument(s[2] - '0'));
 386         if (s == "boxed")
 387                 return MathAtom(new InsetMathBoxed(buf));
 388         if (s == "fbox")
 389                 return MathAtom(new InsetMathFBox(buf));
 390         if (s == "framebox")
 391                 return MathAtom(new InsetMathMakebox(buf, true));
 392         if (s == "makebox")
 393                 return MathAtom(new InsetMathMakebox(buf, false));
 394         if (s == "kern")
 395                 return MathAtom(new InsetMathKern);
 396         if (s.substr(0, 8) == "xymatrix") {
 397                 char spacing_code = '\0';
 398                 Length spacing;
 399                 bool equal_spacing = false;
 400                 size_t const len = s.length();
 401                 size_t i = 8;
 402                 if (i < len && s[i] == '@') {
 403                         ++i;
 404                         if (i < len && s[i] == '!') {
 405                                 equal_spacing = true;
 406                                 ++i;
 407                                 if (i < len) {
 408                                         switch (s[i]) {
 409                                         case '0':
 410                                         case 'R':
 411                                         case 'C':
 412                                                 spacing_code = static_cast<char>(s[i]);
 413                                         }
 414                                 }
 415                         } else if (i < len) {
 416                                 switch (s[i]) {
 417                                 case 'R':
 418                                 case 'C':
 419                                 case 'M':
 420                                 case 'W':
 421                                 case 'H':
 422                                 case 'L':
 423                                         spacing_code = static_cast<char>(s[i]);
 424                                         ++i;
 425                                         break;
 426                                 }
 427                                 if (i < len && s[i] == '=') {
 428                                         ++i;
 429                                         spacing = Length(to_ascii(s.substr(i)));
 430                                 }
 431                         }
 432                 }
 433                 return MathAtom(new InsetMathXYMatrix(buf, spacing, spacing_code,
 434                         equal_spacing));
 435         }
 436
 437         if (s == "Diagram")
 438                 return MathAtom(new InsetMathDiagram(buf));
 439         if (s == "xrightarrow" || s == "xleftarrow")
 440                 return MathAtom(new InsetMathXArrow(buf, s));
 441         if (s == "split" || s == "alignedat")
 442                 return MathAtom(new InsetMathSplit(buf, s));
 443         if (s == "cases")
 444                 return MathAtom(new InsetMathCases(buf));
 445         if (s == "substack")
 446                 return MathAtom(new InsetMathSubstack(buf));
 447         if (s == "subarray" || s == "array")
 448                 return MathAtom(new InsetMathArray(buf, s, 1, 1));
 449         if (s == "sqrt")
 450                 return MathAtom(new InsetMathSqrt(buf));
 451         if (s == "root")
 452                 return MathAtom(new InsetMathRoot(buf));
 453         if (s == "tabular")
 454                 return MathAtom(new InsetMathTabular(buf, s, 1, 1));
 455         if (s == "stackrel")
 456                 return MathAtom(new InsetMathStackrel(buf));
 457         if (s == "binom")
 458                 return MathAtom(new InsetMathBinom(buf, InsetMathBinom::BINOM));
 459         if (s == "dbinom")
 460                 return MathAtom(new InsetMathBinom(buf, InsetMathBinom::DBINOM));
 461         if (s == "tbinom")
 462                 return MathAtom(new InsetMathBinom(buf, InsetMathBinom::TBINOM));
 463         if (s == "choose")
 464                 return MathAtom(new InsetMathBinom(buf, InsetMathBinom::CHOOSE));
 465         if (s == "brace")
 466                 return MathAtom(new InsetMathBinom(buf, InsetMathBinom::BRACE));
 467         if (s == "brack")
 468                 return MathAtom(new InsetMathBinom(buf, InsetMathBinom::BRACK));
 469         if (s == "frac")
 470                 return MathAtom(new InsetMathFrac(buf));
 471         if (s == "cfrac")
 472                 return MathAtom(new InsetMathFrac(buf, InsetMathFrac::CFRAC));
 473         if (s == "dfrac")
 474                 return MathAtom(new InsetMathFrac(buf, InsetMathFrac::DFRAC));
 475         if (s == "tfrac")
 476                 return MathAtom(new InsetMathFrac(buf, InsetMathFrac::TFRAC));
 477         if (s == "over")
 478                 return MathAtom(new InsetMathFrac(buf, InsetMathFrac::OVER));
 479         if (s == "nicefrac")
 480                 return MathAtom(new InsetMathFrac(buf, InsetMathFrac::NICEFRAC));
 481         if (s == "unitfrac")
 482                 return MathAtom(new InsetMathFrac(buf, InsetMathFrac::UNITFRAC));
 483         // These string values are only for math toolbar use, no LaTeX names
 484         if (s == "unitfracthree")
 485                 return MathAtom(new InsetMathFrac(buf, InsetMathFrac::UNITFRAC, 3));
 486         if (s == "unitone")
 487                 return MathAtom(new InsetMathFrac(buf, InsetMathFrac::UNIT, 1));
 488         if (s == "unittwo")
 489                 return MathAtom(new InsetMathFrac(buf, InsetMathFrac::UNIT));
 490         if (s == "cfracleft")
 491                 return MathAtom(new InsetMathFrac(buf, InsetMathFrac::CFRACLEFT));
 492         if (s == "cfracright")
 493                 return MathAtom(new InsetMathFrac(buf, InsetMathFrac::CFRACRIGHT));
 494         //if (s == "infer")
 495         //      return MathAtom(new MathInferInset);
 496         if (s == "atop")
 497                 return MathAtom(new InsetMathFrac(buf, InsetMathFrac::ATOP));
 498         if (s == "lefteqn")
 499                 return MathAtom(new InsetMathLefteqn(buf));
 500         if (s == "boldsymbol")
 501                 return MathAtom(new InsetMathBoldSymbol(buf, InsetMathBoldSymbol::AMS_BOLD));
 502         if (s == "bm")
 503                 return MathAtom(new InsetMathBoldSymbol(buf, InsetMathBoldSymbol::BM_BOLD));
 504         if (s == "heavysymbol" || s == "hm")
 505                 return MathAtom(new InsetMathBoldSymbol(buf, InsetMathBoldSymbol::BM_HEAVY));
 506         if (s == "color" || s == "normalcolor")
 507                 return MathAtom(new InsetMathColor(buf, true));
 508         if (s == "textcolor")
 509                 return MathAtom(new InsetMathColor(buf, false));
 510         if (s == "hphantom")
 511                 return MathAtom(new InsetMathPhantom(buf, InsetMathPhantom::hphantom));
 512         if (s == "phantom")
 513                 return MathAtom(new InsetMathPhantom(buf, InsetMathPhantom::phantom));
 514         if (s == "vphantom")
 515                 return MathAtom(new InsetMathPhantom(buf, InsetMathPhantom::vphantom));
 516         if (s == "cancel")
 517                 return MathAtom(new InsetMathCancel(buf, InsetMathCancel::cancel));
 518         if (s == "bcancel")
 519                 return MathAtom(new InsetMathCancel(buf, InsetMathCancel::bcancel));
 520         if (s == "xcancel")
 521                 return MathAtom(new InsetMathCancel(buf, InsetMathCancel::xcancel));
 522         if (s == "cancelto")
 523                 return MathAtom(new InsetMathCancelto(buf));
 524         if (s == "smash")
 525                 return MathAtom(new InsetMathPhantom(buf, InsetMathPhantom::smash));
 526         if (s == "mathclap")
 527                 return MathAtom(new InsetMathPhantom(buf, InsetMathPhantom::mathclap));
 528         if (s == "mathllap")
 529                 return MathAtom(new InsetMathPhantom(buf, InsetMathPhantom::mathllap));
 530         if (s == "mathrlap")
 531                 return MathAtom(new InsetMathPhantom(buf, InsetMathPhantom::mathrlap));
 532         if (s == "ensuremath")
 533                 return MathAtom(new InsetMathEnsureMath(buf));
 534         if (isSpecialChar(s))
 535                 return MathAtom(new InsetMathSpecialChar(s));
 536         if (s == " ")
 537                 return MathAtom(new InsetMathSpace(" ", ""));
 538
 539         if (s == "regexp")
 540                 return MathAtom(new InsetMathHull(buf, hullRegexp));
 541
 542         return MathAtom(new MathMacro(buf, s));
 543 }
 544
 545
 546 bool createInsetMath_fromDialogStr(docstring const & str, MathData & ar)
 547 {
 548         // An example str:
 549         // "ref LatexCommand ref\nreference \"sec:Title\"\n\\end_inset\n\n";
 550         docstring name;
 551         docstring body = split(str, name, ' ');
 552
 553         if (name == "ref") {
 554                 InsetCommandParams icp(REF_CODE);
 555                 // FIXME UNICODE
 556                 InsetCommand::string2params(to_utf8(str), icp);
 557                 Encoding const * const utf8 = encodings.fromLyXName("utf8");
 558                 OutputParams op(utf8);
 559                 mathed_parse_cell(ar, icp.getCommand(op));
 560         } else if (name == "mathspace") {
 561                 InsetSpaceParams isp(true);
 562                 InsetSpace::string2params(to_utf8(str), isp);
 563                 InsetSpace is(isp);
 564                 TexRow texrow;
 565                 odocstringstream ods;
 566                 otexstream os(ods, texrow);
 567                 Encoding const * const ascii = encodings.fromLyXName("ascii");
 568                 OutputParams op(ascii);
 569                 is.latex(os, op);
 570                 mathed_parse_cell(ar, ods.str());
 571                 if (ar.size() == 2) {
 572                         // remove "{}"
 573                         if (ar[1].nucleus()->asBraceInset())
 574                                 ar.pop_back();
 575                 }
 576         } else
 577                 return false;
 578
 579         if (ar.size() != 1)
 580                 return false;
 581
 582         return ar[0].nucleus();
 583 }
 584
 585
 586 bool isAsciiOrMathAlpha(char_type c)
 587 {
 588         return c < 0x80 || Encodings::isMathAlpha(c);
 589 }
 590
 591
 592 } // namespace lyx