src/stc/scintilla/src/LexGAP.cxx

   1 // Scintilla source code edit control
   2 /** @file LexGAP.cxx
   3  ** Lexer for the GAP language. (The GAP System for Computational Discrete Algebra)
   4  ** http://www.gap-system.org
   5  **/
   6 // Copyright 2007 by Istvan Szollosi ( szteven <at> gmail <dot> com )
   7 // The License.txt file describes the conditions under which this software may be distributed.
   8
   9 #include <stdlib.h>
  10 #include <string.h>
  11 #include <ctype.h>
  12 #include <stdio.h>
  13 #include <stdarg.h>
  14
  15 #include "Platform.h"
  16
  17 #include "PropSet.h"
  18 #include "Accessor.h"
  19 #include "StyleContext.h"
  20 #include "KeyWords.h"
  21 #include "Scintilla.h"
  22 #include "SciLexer.h"
  23
  24 #ifdef SCI_NAMESPACE
  25 using namespace Scintilla;
  26 #endif
  27
  28 static inline bool IsGAPOperator(char ch) {
  29         if (isalnum(ch)) return false;
  30         if (ch == '+' || ch == '-' || ch == '*' || ch == '/' ||
  31                 ch == '^' || ch == ',' || ch == '!' || ch == '.' ||
  32                 ch == '=' || ch == '<' || ch == '>' || ch == '(' ||
  33                 ch == ')' || ch == ';' || ch == '[' || ch == ']' ||
  34                 ch == '{' || ch == '}' || ch == ':' )
  35                 return true;
  36         return false;
  37 }
  38
  39 static void GetRange(unsigned int start, unsigned int end, Accessor &styler, char *s, unsigned int len) {
  40         unsigned int i = 0;
  41         while ((i < end - start + 1) && (i < len-1)) {
  42                 s[i] = static_cast<char>(styler[start + i]);
  43                 i++;
  44         }
  45         s[i] = '\0';
  46 }
  47
  48 static void ColouriseGAPDoc(unsigned int startPos, int length, int initStyle, WordList *keywordlists[], Accessor &styler) {
  49
  50         WordList &keywords1 = *keywordlists[0];
  51         WordList &keywords2 = *keywordlists[1];
  52         WordList &keywords3 = *keywordlists[2];
  53         WordList &keywords4 = *keywordlists[3];
  54
  55         // Do not leak onto next line
  56         if (initStyle == SCE_GAP_STRINGEOL) initStyle = SCE_GAP_DEFAULT;
  57
  58         StyleContext sc(startPos, length, initStyle, styler);
  59
  60         for (; sc.More(); sc.Forward()) {
  61
  62                 // Prevent SCE_GAP_STRINGEOL from leaking back to previous line
  63                 if ( sc.atLineStart ) {
  64                         if (sc.state == SCE_GAP_STRING) sc.SetState(SCE_GAP_STRING);
  65                         if (sc.state == SCE_GAP_CHAR) sc.SetState(SCE_GAP_CHAR);
  66                 }
  67
  68                 // Handle line continuation generically
  69                 if (sc.ch == '\\' ) {
  70                         if (sc.chNext == '\n' || sc.chNext == '\r') {
  71                                 sc.Forward();
  72                                 if (sc.ch == '\r' && sc.chNext == '\n') {
  73                                         sc.Forward();
  74                                 }
  75                                 continue;
  76                         }
  77                 }
  78
  79                 // Determine if the current state should terminate
  80                 switch (sc.state) {
  81                         case SCE_GAP_OPERATOR :
  82                                 sc.SetState(SCE_GAP_DEFAULT);
  83                                 break;
  84
  85                         case SCE_GAP_NUMBER :
  86                                 if (!IsADigit(sc.ch)) {
  87                                         if (sc.ch == '\\') {
  88                                                 if (!sc.atLineEnd) {
  89                                                         if (!IsADigit(sc.chNext)) {
  90                                                                 sc.Forward();
  91                                                                 sc.ChangeState(SCE_GAP_IDENTIFIER);
  92                                                         }
  93                                                 }
  94                                         } else if (isalpha(sc.ch) || sc.ch == '_') {
  95                                                 sc.ChangeState(SCE_GAP_IDENTIFIER);
  96                                         }
  97                                         else sc.SetState(SCE_GAP_DEFAULT);
  98                                 }
  99                                 break;
 100
 101                         case SCE_GAP_IDENTIFIER :
 102                                 if (!(iswordstart(static_cast<char>(sc.ch)) || sc.ch == '$')) {
 103                                         if (sc.ch == '\\') sc.Forward();
 104                                         else {
 105                                                 char s[1000];
 106                                                 sc.GetCurrent(s, sizeof(s));
 107                                                 if (keywords1.InList(s)) {
 108                                                         sc.ChangeState(SCE_GAP_KEYWORD);
 109                                                 } else if (keywords2.InList(s)) {
 110                                                         sc.ChangeState(SCE_GAP_KEYWORD2);
 111                                                 } else if (keywords3.InList(s)) {
 112                                                         sc.ChangeState(SCE_GAP_KEYWORD3);
 113                                                 } else if (keywords4.InList(s)) {
 114                                                         sc.ChangeState(SCE_GAP_KEYWORD4);
 115                                                 }
 116                                                 sc.SetState(SCE_GAP_DEFAULT);
 117                                         }
 118                                 }
 119                                 break;
 120
 121                         case SCE_GAP_COMMENT :
 122                                 if (sc.atLineEnd) {
 123                                         sc.SetState(SCE_GAP_DEFAULT);
 124                                 }
 125                                 break;
 126
 127                         case SCE_GAP_STRING:
 128                                 if (sc.atLineEnd) {
 129                                         sc.ChangeState(SCE_GAP_STRINGEOL);
 130                                 } else if (sc.ch == '\\') {
 131                                         if (sc.chNext == '\"' || sc.chNext == '\'' || sc.chNext == '\\') {
 132                                                 sc.Forward();
 133                                         }
 134                                 } else if (sc.ch == '\"') {
 135                                         sc.ForwardSetState(SCE_GAP_DEFAULT);
 136                                 }
 137                                 break;
 138
 139                         case SCE_GAP_CHAR:
 140                                 if (sc.atLineEnd) {
 141                                         sc.ChangeState(SCE_GAP_STRINGEOL);
 142                                 } else if (sc.ch == '\\') {
 143                                         if (sc.chNext == '\"' || sc.chNext == '\'' || sc.chNext == '\\') {
 144                                                 sc.Forward();
 145                                         }
 146                                 } else if (sc.ch == '\'') {
 147                                         sc.ForwardSetState(SCE_GAP_DEFAULT);
 148                                 }
 149                                 break;
 150
 151                         case SCE_GAP_STRINGEOL:
 152                                 if (sc.atLineStart) {
 153                                         sc.SetState(SCE_GAP_DEFAULT);
 154                                 }
 155                                 break;
 156                 }
 157
 158                 // Determine if a new state should be entered
 159                 if (sc.state == SCE_GAP_DEFAULT) {
 160                         if (IsGAPOperator(static_cast<char>(sc.ch))) {
 161                                 sc.SetState(SCE_GAP_OPERATOR);
 162                         }
 163                         else if (IsADigit(sc.ch)) {
 164                                 sc.SetState(SCE_GAP_NUMBER);
 165                         } else if (isalpha(sc.ch) || sc.ch == '_' || sc.ch == '\\' || sc.ch == '$' || sc.ch == '~') {
 166                                 sc.SetState(SCE_GAP_IDENTIFIER);
 167                                 if (sc.ch == '\\') sc.Forward();
 168                         } else if (sc.ch == '#') {
 169                                 sc.SetState(SCE_GAP_COMMENT);
 170                         } else if (sc.ch == '\"') {
 171                                 sc.SetState(SCE_GAP_STRING);
 172                         } else if (sc.ch == '\'') {
 173                                 sc.SetState(SCE_GAP_CHAR);
 174                         }
 175                 }
 176
 177         }
 178         sc.Complete();
 179 }
 180
 181 static int ClassifyFoldPointGAP(const char* s) {
 182         int level = 0;
 183         if (strcmp(s, "function") == 0 ||
 184                 strcmp(s, "do") == 0 ||
 185                 strcmp(s, "if") == 0 ||
 186                 strcmp(s, "repeat") == 0 ) {
 187                 level = 1;
 188         } else if (strcmp(s, "end") == 0 ||
 189                         strcmp(s, "od") == 0 ||
 190                         strcmp(s, "fi") == 0 ||
 191                         strcmp(s, "until") == 0 ) {
 192                 level = -1;
 193         }
 194         return level;
 195 }
 196
 197 static void FoldGAPDoc( unsigned int startPos, int length, int initStyle,   WordList** , Accessor &styler) {
 198         unsigned int endPos = startPos + length;
 199         int visibleChars = 0;
 200         int lineCurrent = styler.GetLine(startPos);
 201         int levelPrev = styler.LevelAt(lineCurrent) & SC_FOLDLEVELNUMBERMASK;
 202         int levelCurrent = levelPrev;
 203         char chNext = styler[startPos];
 204         int styleNext = styler.StyleAt(startPos);
 205         int style = initStyle;
 206
 207         int lastStart = 0;
 208
 209         for (unsigned int i = startPos; i < endPos; i++) {
 210                 char ch = chNext;
 211                 chNext = styler.SafeGetCharAt(i + 1);
 212                 int stylePrev = style;
 213                 style = styleNext;
 214                 styleNext = styler.StyleAt(i + 1);
 215                 bool atEOL = (ch == '\r' && chNext != '\n') || (ch == '\n');
 216
 217                 if (stylePrev != SCE_GAP_KEYWORD && style == SCE_GAP_KEYWORD) {
 218                         // Store last word start point.
 219                         lastStart = i;
 220                 }
 221
 222                 if (stylePrev == SCE_GAP_KEYWORD) {
 223                         if(iswordchar(ch) && !iswordchar(chNext)) {
 224                                 char s[100];
 225                                 GetRange(lastStart, i, styler, s, sizeof(s));
 226                                 levelCurrent += ClassifyFoldPointGAP(s);
 227                         }
 228                 }
 229
 230                 if (atEOL) {
 231                         int lev = levelPrev;
 232                         if ((levelCurrent > levelPrev) && (visibleChars > 0))
 233                                 lev |= SC_FOLDLEVELHEADERFLAG;
 234                         if (lev != styler.LevelAt(lineCurrent)) {
 235                                 styler.SetLevel(lineCurrent, lev);
 236                         }
 237                         lineCurrent++;
 238                         levelPrev = levelCurrent;
 239                         visibleChars = 0;
 240                 }
 241
 242                 if (!isspacechar(ch))
 243                         visibleChars++;
 244         }
 245
 246         int flagsNext = styler.LevelAt(lineCurrent) & ~SC_FOLDLEVELNUMBERMASK;
 247         styler.SetLevel(lineCurrent, levelPrev | flagsNext);
 248 }
 249
 250 static const char * const GAPWordListDesc[] = {
 251         "Keywords 1",
 252         "Keywords 2",
 253         "Keywords 3 (unused)",
 254         "Keywords 4 (unused)",
 255         0
 256 };
 257
 258 LexerModule lmGAP(
 259    SCLEX_GAP,
 260    ColouriseGAPDoc,
 261    "gap",
 262    FoldGAPDoc,
 263    GAPWordListDesc);