src/tex2lyx/math.C

   1 /**
   2  * \file math.C
   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 // {[(
  12
  13 #include <config.h>
  14
  15 #include "tex2lyx.h"
  16
  17 #include <iostream>
  18
  19 using std::cerr;
  20 using std::endl;
  21
  22 using std::ostream;
  23 using std::string;
  24
  25
  26 bool is_math_env(string const & name)
  27 {
  28         static char const * const known_math_envs[] = { "equation",
  29         "equation*", "eqnarray", "eqnarray*", "align", "align*", "gather",
  30         "gather*", "multline", "multline*", "math", "displaymath", "flalign",
  31         "flalign*",
  32         // These require extra args
  33         "alignat", "alignat*", "xalignat", "xalignat*", "xxalignat",
  34         0};
  35
  36         for (char const * const * what = known_math_envs; *what; ++what)
  37                 if (*what == name)
  38                         return true;
  39         return false;
  40 }
  41
  42
  43 void parse_math(Parser & p, ostream & os, unsigned flags, const mode_type mode)
  44 {
  45         while (p.good()) {
  46                 Token const & t = p.get_token();
  47
  48 #ifdef FILEDEBUG
  49                 cerr << "t: " << t << " flags: " << flags << "\n";
  50 #endif
  51
  52                 if (flags & FLAG_ITEM) {
  53                         if (t.cat() == catSpace)
  54                                 continue;
  55
  56                         flags &= ~FLAG_ITEM;
  57                         if (t.cat() == catBegin) {
  58                                 // skip the brace and collect everything to the next matching
  59                                 // closing brace
  60                                 flags |= FLAG_BRACE_LAST;
  61                                 continue;
  62                         }
  63
  64                         // handle only this single token, leave the loop if done
  65                         flags |= FLAG_LEAVE;
  66                 }
  67
  68
  69                 //
  70                 // cat codes
  71                 //
  72                 if (t.cat() == catMath) {
  73                         if (mode == MATHTEXT_MODE) {
  74                                 // we are inside some text mode thingy, so opening new math is allowed
  75                                 Token const & n = p.get_token();
  76                                 if (n.cat() == catMath) {
  77                                         // TeX's $$...$$ syntax for displayed math
  78                                         os << "\\[";
  79                                         parse_math(p, os, FLAG_SIMPLE, MATH_MODE);
  80                                         os << "\\]";
  81                                         p.get_token(); // skip the second '$' token
  82                                 } else {
  83                                         // simple $...$  stuff
  84                                         p.putback();
  85                                         os << '$';
  86                                         parse_math(p, os, FLAG_SIMPLE, MATH_MODE);
  87                                         os << '$';
  88                                 }
  89                         }
  90
  91                         else if (flags & FLAG_SIMPLE) {
  92                                 // this is the end of the formula
  93                                 return;
  94                         }
  95
  96                         else {
  97                                 cerr << "\nmode: " << mode << endl;
  98                                 p.error("something strange in the parser\n");
  99                                 break;
 100                         }
 101                 }
 102
 103                 else if (t.cat() == catLetter ||
 104                                t.cat() == catSuper ||
 105                                t.cat() == catSub ||
 106                                t.cat() == catOther ||
 107                                t.cat() == catAlign ||
 108                                t.cat() == catActive ||
 109                                t.cat() == catParameter)
 110                         os << t.character();
 111
 112                 else if (t.cat() == catBegin) {
 113                         os << '{';
 114                         parse_math(p, os, FLAG_BRACE_LAST, mode);
 115                         os << '}';
 116                 }
 117
 118                 else if (t.cat() == catEnd) {
 119                         if (flags & FLAG_BRACE_LAST)
 120                                 return;
 121                         os << "unexpected '}' in math\n";
 122                 }
 123
 124                 else if (t.cat() == catComment) {
 125                         if (!t.cs().empty())
 126                                 cerr << "Ignoring comment: " << t.asInput();
 127                         else
 128                                 // "%\n" combination
 129                                 p.skip_spaces();
 130                 }
 131
 132                 //
 133                 // control sequences
 134                 //
 135
 136                 else if (t.cs() == "(") {
 137                         os << "\\(";
 138                         parse_math(p, os, FLAG_SIMPLE2, MATH_MODE);
 139                         os << "\\)";
 140                 }
 141
 142                 else if (t.cs() == "[") {
 143                         // special handling of a few common SW user quirks
 144                         p.skip_spaces();
 145                         //if (p.next_token().cs() ==
 146                         os << "\\[";
 147                         parse_math(p, os, FLAG_EQUATION, MATH_MODE);
 148                         os << "\\]";
 149                 }
 150
 151                 else if (t.cs() == "protect")
 152                         // ignore \\protect, will hopefully be re-added during output
 153                         ;
 154
 155                 else if (t.cs() == "begin") {
 156                         string const name = p.getArg('{', '}');
 157                         active_environments.push_back(name);
 158                         os << "\\begin{" << name << "}";
 159                         if (name == "tabular")
 160                                 parse_math(p, os, FLAG_END, MATHTEXT_MODE);
 161                         else
 162                                 parse_math(p, os, FLAG_END, mode);
 163                         os << "\\end{" << name << "}";
 164                         active_environments.pop_back();
 165                 }
 166
 167                 else if (t.cs() == "end") {
 168                         if (flags & FLAG_END) {
 169                                 // eat environment name
 170                                 string const name = p.getArg('{', '}');
 171                                 if (name != active_environment())
 172                                         p.error("\\end{" + name + "} does not match \\begin{"
 173                                                 + active_environment() + "}");
 174                                 return;
 175                         }
 176                         p.error("found 'end' unexpectedly");
 177                 }
 178
 179                 else if (t.cs() == ")") {
 180                         if (flags & FLAG_SIMPLE2)
 181                                 return;
 182                         p.error("found '\\)' unexpectedly");
 183                 }
 184
 185                 else if (t.cs() == "]") {
 186                         if (flags & FLAG_EQUATION)
 187                                 return;
 188                         p.error("found '\\]' unexpectedly");
 189                 }
 190
 191                 else if (t.cs() == "textrm" || t.cs() == "textsf" || t.cs() == "textbf"
 192                                 || t.cs() == "texttt" || t.cs() == "textsc"
 193                                 || t.cs() == "text" || t.cs() == "intertext") {
 194                         os << '\\' << t.cs() << '{';
 195                         parse_math(p, os, FLAG_ITEM, MATHTEXT_MODE);
 196                         os << '}';
 197                 }
 198
 199                 else if (t.cs() == "mbox" || t.cs() == "fbox") {
 200                         os << "\\" << t.cs() << '{';
 201                         parse_math(p, os, FLAG_ITEM, MATHTEXT_MODE);
 202                         os << '}';
 203                 }
 204
 205                 else if (t.cs() == "\"") {
 206                         string const name = p.verbatim_item();
 207                              if (name == "a") os << 'ä';
 208                         else if (name == "o") os << 'ö';
 209                         else if (name == "u") os << 'ü';
 210                         else if (name == "A") os << 'Ä';
 211                         else if (name == "O") os << 'Ö';
 212                         else if (name == "U") os << 'Ü';
 213                         else os << "\"{" << name << "}";
 214                 }
 215
 216                 else if (t.cs() == "ss")
 217                         os << "ß";
 218
 219                 else if (t.cs() == "cr") {
 220                         // lyx can't handle \\cr
 221                         cerr << "Warning: Converting TeX '\\cr' to LaTeX '\\\\'."
 222                              << endl;
 223                         os << "\\\\";
 224                 }
 225
 226                 else
 227                         os << t.asInput();
 228
 229                 if (flags & FLAG_LEAVE) {
 230                         flags &= ~FLAG_LEAVE;
 231                         break;
 232                 }
 233         }
 234 }
 235
 236
 237
 238
 239 // }])