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