Beispiel #1
0
 void Init()
 {
     pos = -1; line = 1; col = 0; charPos = -1;
     oldEols = 0;
     NextCh();
     if (ch == 0xEF) { // check optional byte order mark for UTF-8
     NextCh(); int ch1 = ch;
     NextCh(); int ch2 = ch;
     if (ch1 != 0xBB || ch2 != 0xBF) {
         throw new FatalError(String.Format("illegal byte order mark: EF {0,2:X} {1,2:X}", ch1, ch2));
     }
     buffer = new UTF8Buffer(buffer); col = 0; charPos = -1;
     NextCh();
     }
     pt = tokens = new Token();  // first token is a dummy
 }
Beispiel #2
0
        Token NextToken()
        {
            while (ch == ' ' ||
            ch >= 9 && ch <= 10 || ch == 13
            ) NextCh();
            if (ch == '/' && Comment0() ||ch == '/' && Comment1()) return NextToken();
            int recKind = noSym;
            int recEnd = pos;
            t = new Token();
            t.pos = pos; t.col = col; t.line = line; t.charPos = charPos;
            int state;
            if (start.ContainsKey(ch)) { state = (int) start[ch]; }
            else { state = 0; }
            tlen = 0; AddCh();

            switch (state) {
            case -1: { t.kind = eofSym; break; } // NextCh already done
            case 0: {
                if (recKind != noSym) {
                    tlen = recEnd - t.pos;
                    SetScannerBehindT();
                }
                t.kind = recKind; break;
            } // NextCh already done
            case 1:
                recEnd = pos; recKind = 1;
                if (ch >= '0' && ch <= '9' || ch >= 'A' && ch <= 'Z' || ch >= 'a' && ch <= 'z') {AddCh(); goto case 1;}
                else {t.kind = 1; t.val = new String(tval, 0, tlen); CheckLiteral(); return t;}
            case 2:
                recEnd = pos; recKind = 2;
                if (ch >= '0' && ch <= '9') {AddCh(); goto case 2;}
                else {t.kind = 2; break;}
            case 3:
                if (ch <= 9 || ch >= 11 && ch <= 12 || ch >= 14 && ch <= '!' || ch >= '#' && ch <= 65535) {AddCh(); goto case 3;}
                else if (ch == '"') {AddCh(); goto case 4;}
                else {goto case 0;}
            case 4:
                {t.kind = 3; break;}
            case 5:
                {t.kind = 4; break;}
            case 6:
                {t.kind = 6; break;}
            case 7:
                {t.kind = 7; break;}
            case 8:
                {t.kind = 13; break;}
            case 9:
                {t.kind = 14; break;}
            case 10:
                {t.kind = 15; break;}
            case 11:
                if (ch == '=') {AddCh(); goto case 12;}
                else {goto case 0;}
            case 12:
                {t.kind = 18; break;}
            case 13:
                {t.kind = 19; break;}
            case 14:
                {t.kind = 20; break;}
            case 15:
                {t.kind = 21; break;}
            case 16:
                {t.kind = 22; break;}
            case 17:
                {t.kind = 27; break;}
            case 18:
                {t.kind = 28; break;}
            case 19:
                {t.kind = 30; break;}
            case 20:
                {t.kind = 31; break;}
            case 21:
                recEnd = pos; recKind = 11;
                if (ch == '+') {AddCh(); goto case 15;}
                else {t.kind = 11; break;}
            case 22:
                recEnd = pos; recKind = 12;
                if (ch == '-') {AddCh(); goto case 16;}
                else if (ch == '>') {AddCh(); goto case 20;}
                else {t.kind = 12; break;}
            case 23:
                recEnd = pos; recKind = 25;
                if (ch == '=') {AddCh(); goto case 10;}
                else {t.kind = 25; break;}
            case 24:
                recEnd = pos; recKind = 16;
                if (ch == '=') {AddCh(); goto case 14;}
                else {t.kind = 16; break;}
            case 25:
                recEnd = pos; recKind = 17;
                if (ch == '=') {AddCh(); goto case 13;}
                else {t.kind = 17; break;}

            }
            t.val = new String(tval, 0, tlen);
            return t;
        }
Beispiel #3
0
 // get the next token (possibly a token already seen during peeking)
 public Token Scan()
 {
     if (tokens.next == null) {
     return NextToken();
     } else {
     pt = tokens = tokens.next;
     return tokens;
     }
 }
Beispiel #4
0
 // make sure that peeking starts at the current scan position
 public void ResetPeek()
 {
     pt = tokens;
 }
Beispiel #5
0
        // peek for the next token, ignore pragmas
        public Token Peek()
        {
            do {
            if (pt.next == null) {
                pt.next = NextToken();
            }
            pt = pt.next;
            } while (pt.kind > maxT); // skip pragmas

            return pt;
        }
Beispiel #6
0
        void Get()
        {
            for (;;) {
            t = la;
            la = scanner.Scan();
            if (la.kind <= maxT) { ++errDist; break; }

            la = t;
            }
        }
Beispiel #7
0
 public void Parse()
 {
     la = new Token();
     la.val = "";
     Get();
     Alf();
     Expect(0);
 }