lextads3.cxx

porting scintilla to qt

                                } else if (IsANumberStart(sc)) {
                                        ColouriseTADS3Number(sc);
                                        visibleChars++;
                                } else if (IsAWordStart(sc.ch)) {
                                        ColouriseTADS3Keyword(sc, keywordlists, endPos);
                                        visibleChars++;
                                } else if (sc.Match("...")) {
                                        sc.SetState(SCE_T3_IDENTIFIER);
                                        sc.Forward(3);
                                        sc.SetState(SCE_T3_DEFAULT);
                                } else {
                                        sc.Forward();
                                        visibleChars++;
                                }
                                break;
                        default:
                                sc.SetState(SCE_T3_DEFAULT);
                                sc.Forward();
                }
        }
        sc.Complete();
}

/*
 TADS3 has two styles of top level block (TLB). Eg

 // default style
 silverKey : Key 'small silver key' 'small silver key'
        "A small key glints in the sunlight. "
 ;

 and

 silverKey : Key {
        'small silver key'
        'small silver key'
        "A small key glints in the sunlight. "
 }

 Some constructs mandate one or the other, but usually the author has may choose
 either.

 T3_SEENSTART is used to indicate that a braceless TLB has been (potentially)
 seen and is also used to match the closing ';' of the default style.

 T3_EXPECTINGIDENTIFIER and T3_EXPECTINGPUNCTUATION are used to keep track of
 what characters may be seen without incrementing the block level.  The general
 pattern is identifier <punc> identifier, acceptable punctuation characters
 are ':', ',', '(' and ')'.  No attempt is made to ensure that punctuation
 characters are syntactically correct, eg parentheses match. A ')' always
 signifies the start of a block.  We just need to check if it is followed by a
 '{', in which case we let the brace handling code handle the folding level.

 expectingIdentifier == false && expectingIdentifier == false
 Before the start of a TLB.

 expectingIdentifier == true && expectingIdentifier == true
 Currently in an identifier.  Will accept identifier or punctuation.

 expectingIdentifier == true && expectingIdentifier == false
 Just seen a punctuation character & now waiting for an identifier to start.

 expectingIdentifier == false && expectingIdentifier == truee
 We were in an identifier and have seen space.  Now waiting to see a punctuation
 character

 Space, comments & preprocessor directives are always acceptable and are
 equivalent.
*/

static const int T3_SEENSTART = 1 << 12;
static const int T3_EXPECTINGIDENTIFIER = 1 << 13;
static const int T3_EXPECTINGPUNCTUATION = 1 << 14;

static inline bool IsStringTransition(int s1, int s2) {
        return s1 != s2
                && (s1 == SCE_T3_S_STRING || s1 == SCE_T3_X_STRING
                        || s1 == SCE_T3_D_STRING && s2 != SCE_T3_X_DEFAULT)
                && s2 != SCE_T3_LIB_DIRECTIVE
                && s2 != SCE_T3_MSG_PARAM
                && s2 != SCE_T3_HTML_TAG
                && s2 != SCE_T3_HTML_STRING;
}

static inline bool IsATADS3Punctuation(const int ch) {
        return ch == ':' || ch == ',' || ch == '(' || ch == ')';
}

static inline bool IsAnIdentifier(const int style) {
        return style == SCE_T3_IDENTIFIER
                || style == SCE_T3_USER1
                || style == SCE_T3_USER2
                || style == SCE_T3_USER3;
}

static inline bool IsAnOperator(const int style) {
    return style == SCE_T3_OPERATOR || SCE_T3_BRACE;
}

static inline bool IsSpaceEquivalent(const int ch, const int style) {
        return isspace(ch)
                || style == SCE_T3_BLOCK_COMMENT
                || style == SCE_T3_LINE_COMMENT
                || style == SCE_T3_PREPROCESSOR;
}

static char peekAhead(unsigned int startPos, unsigned int endPos,
                                          Accessor &styler) {
        for (unsigned int i = startPos; i < endPos; i++) {
                int style = styler.StyleAt(i);
                char ch = styler[i];
                if (!IsSpaceEquivalent(ch, style)) {
                        if (IsAnIdentifier(style)) {
                                return 'a';
                        }
                        if (IsATADS3Punctuation(ch)) {
                                return ':';
                        }
                        if (ch == '{') {
                                return '{';
                        }
                        return '*';
                }
        }
        return ' ';
}

static void FoldTADS3Doc(unsigned int startPos, int length, int initStyle,
                            WordList *[], Accessor &styler) {
        unsigned int endPos = startPos + length;
        int lineCurrent = styler.GetLine(startPos);
        int levelCurrent = SC_FOLDLEVELBASE;
        if (lineCurrent > 0)
                levelCurrent = styler.LevelAt(lineCurrent-1) >> 16;
        int seenStart = levelCurrent & T3_SEENSTART;
        int expectingIdentifier = levelCurrent & T3_EXPECTINGIDENTIFIER;
        int expectingPunctuation = levelCurrent & T3_EXPECTINGPUNCTUATION;
        levelCurrent &= SC_FOLDLEVELNUMBERMASK;
        int levelMinCurrent = levelCurrent;
        int levelNext = levelCurrent;
        char chNext = styler[startPos];
        int styleNext = styler.StyleAt(startPos);
        int style = initStyle;
        char ch = chNext;
        int stylePrev = style;
        bool redo = false;
        for (unsigned int i = startPos; i < endPos; i++) {
                if (redo) {
                        redo = false;
                        i--;
                } else {
                        ch = chNext;
                        chNext = styler.SafeGetCharAt(i + 1);
                        stylePrev = style;
                        style = styleNext;
                        styleNext = styler.StyleAt(i + 1);
                }
                bool atEOL = IsEOL(ch, chNext);

                if (levelNext == SC_FOLDLEVELBASE) {
                        if (IsSpaceEquivalent(ch, style)) {
                                if (expectingPunctuation) {
                                        expectingIdentifier = 0;
                                }
                                if (style == SCE_T3_BLOCK_COMMENT) {
                                        levelNext++;
                                }
                        } else if (ch == '{') {
                                levelNext++;
                                seenStart = 0;
                        } else if (ch == '\'' || ch == '"' || ch == '[') {
                                levelNext++;
                                if (seenStart) {
                                        redo = true;
                                }
                        } else if (ch == ';') {
                                seenStart = 0;
                                expectingIdentifier = 0;
                                expectingPunctuation = 0;
                        } else if (expectingIdentifier && expectingPunctuation) {
                                if (IsATADS3Punctuation(ch)) {
                                        if (ch == ')' && peekAhead(i+1, endPos, styler) != '{') {
                                                levelNext++;
                                        } else {
                                                expectingPunctuation = 0;
                                        }
                                } else if (!IsAnIdentifier(style)) {
                                        levelNext++;
                                }
                        } else if (expectingIdentifier && !expectingPunctuation) {
                                if (!IsAnIdentifier(style)) {
                                        levelNext++;
                                } else {
                                        expectingPunctuation = T3_EXPECTINGPUNCTUATION;
                                }
                        } else if (!expectingIdentifier && expectingPunctuation) {
                                if (!IsATADS3Punctuation(ch)) {
                                        levelNext++;
                                } else {
                                        if (ch == ')' && peekAhead(i+1, endPos, styler) != '{') {
                                                levelNext++;
                                        } else {
                                                expectingIdentifier = T3_EXPECTINGIDENTIFIER;
                                                expectingPunctuation = 0;
                                        }
                                }
                        } else if (!expectingIdentifier && !expectingPunctuation) {
                                if (IsAnIdentifier(style)) {
                                        seenStart = T3_SEENSTART;
                                        expectingIdentifier = T3_EXPECTINGIDENTIFIER;
                                        expectingPunctuation = T3_EXPECTINGPUNCTUATION;
                                }
                        }

                        if (levelNext != SC_FOLDLEVELBASE && style != SCE_T3_BLOCK_COMMENT) {
                                expectingIdentifier = 0;
                                expectingPunctuation = 0;
                        }

                } else if (levelNext == SC_FOLDLEVELBASE+1 && seenStart
                                   && ch == ';' && IsAnOperator(style)) {
                        levelNext--;
                        seenStart = 0;
                } else if (style == SCE_T3_BLOCK_COMMENT) {
                        if (stylePrev != SCE_T3_BLOCK_COMMENT) {
                                levelNext++;
                        } else if (styleNext != SCE_T3_BLOCK_COMMENT && !atEOL) {
                                // Comments don't end at end of line and the next character may be unstyled.
                                levelNext--;
                        }
                } else if (ch == '\'' || ch == '"') {
                        if (IsStringTransition(style, stylePrev)) {
                                if (levelMinCurrent > levelNext) {
                                        levelMinCurrent = levelNext;
                                }
                                levelNext++;
                        } else if (IsStringTransition(style, styleNext)) {
                                levelNext--;
                        }
                } else if (IsAnOperator(style)) {
                        if (ch == '{' || ch == '[') {
                                // Measure the minimum before a '{' to allow
                                // folding on "} else {"
                                if (levelMinCurrent > levelNext) {
                                        levelMinCurrent = levelNext;
                                }
                                levelNext++;
                        } else if (ch == '}' || ch == ']') {
                                levelNext--;
                        }
                }

                if (atEOL) {
                        if (seenStart && levelNext == SC_FOLDLEVELBASE) {
                                switch (peekAhead(i+1, endPos, styler)) {
                                        case ' ':
                                        case '{':
                                                break;
                                        case '*':
                                                levelNext++;
                                                break;
                                        case 'a':
                                                if (expectingPunctuation) {
                                                        levelNext++;
                                                }
                                                break;
                                        case ':':
                                                if (expectingIdentifier) {
                                                        levelNext++;
                                                }
                                                break;
                                }
                                if (levelNext != SC_FOLDLEVELBASE) {
                                        expectingIdentifier = 0;
                                        expectingPunctuation = 0;
                                }
                        }
                        int lev = levelMinCurrent | (levelNext | expectingIdentifier
                                | expectingPunctuation | seenStart) << 16;
                        if (levelMinCurrent < levelNext)
                                lev |= SC_FOLDLEVELHEADERFLAG;
                        if (lev != styler.LevelAt(lineCurrent)) {
                                styler.SetLevel(lineCurrent, lev);
                        }
                        lineCurrent++;
                        levelCurrent = levelNext;
                        levelMinCurrent = levelCurrent;
                }
        }
}

static const char * const tads3WordList[] = {
        "TADS3 Keywords",
        "User defined 1",
        "User defined 2",
        "User defined 3",
        0
};

LexerModule lmTADS3(SCLEX_TADS3, ColouriseTADS3Doc, "tads3", FoldTADS3Doc, tads3WordList);