public void Parse()
{
la = new Token();
la.val = "";
Get();
Formula();
Expect(0);
}
void Get()
{
for (;;) {
t = la;
la = scanner.Scan();
if (la.kind <= maxT) { ++errDist; break; }
la = t;
}
}
Token NextToken()
{
while (ch == ' ' ||
ch == 10 || ch == 13
) NextCh();
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') {AddCh(); goto case 1;}
else {t.kind = 1; break;}
case 2:
recEnd = pos; recKind = 2;
if (ch >= '0' && ch <= '9' || ch >= 'A' && ch <= 'Z' || ch >= 'a' && ch <= 'z') {AddCh(); goto case 2;}
else {t.kind = 2; break;}
case 3:
{t.kind = 3; break;}
case 4:
{t.kind = 4; break;}
case 5:
{t.kind = 5; break;}
case 6:
{t.kind = 6; break;}
case 7:
{t.kind = 7; break;}
case 8:
{t.kind = 8; break;}
case 9:
{t.kind = 9; break;}
case 10:
{t.kind = 10; break;}
case 11:
{t.kind = 11; break;}
case 12:
{t.kind = 12; break;}
case 13:
{t.kind = 13; break;}
}
t.val = new String(tval, 0, tlen);
return t;
}
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
}
// 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;
}
}
// make sure that peeking starts at the current scan position
public void ResetPeek()
{
pt = tokens;
}
// 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;
}