|
public MatchLiteral ( string s, |
||
| s | string | |
| sym | ||
| return | void | |
static void Factor(out Graph g)
{
string name; int kind; Position pos; bool weak = false;
g = null;
switch (la.kind)
{
case 1:
case 3:
case 5:
case 27: {
if (la.kind == 27)
{
Get();
weak = true;
}
Sym(out name, out kind);
Symbol sym = Symbol.Find(name);
bool undef = sym == null;
if (undef)
{
if (kind == id)
{
sym = new Symbol(Node.nt, name, 0); // forward nt
}
else if (genScanner)
{
sym = new Symbol(Node.t, name, t.line);
DFA.MatchLiteral(sym);
}
else // undefined string in production
{
SemErr("undefined string in production");
sym = Tab.eofSy; // dummy
}
}
int typ = sym.typ;
if (typ != Node.t && typ != Node.nt && typ != Node.rslv) /* ML */
{
SemErr("this symbol kind is not allowed in a production");
}
if (weak)
{
if (typ == Node.t)
{
typ = Node.wt;
}
else
{
SemErr("only terminals may be weak");
}
}
Node p = new Node(typ, sym, t.line);
g = new Graph(p);
if (la.kind == 24)
{
Attribs(p);
if (kind != id)
{
SemErr("a literal must not have attributes");
}
}
if (undef)
{
sym.attrPos = p.pos; // dummy
}
else if ((p.pos == null) != (sym.attrPos == null))
{
SemErr("attribute mismatch between declaration and use of this symbol");
}
break;
}
case 28: {
Get();
Expression(out g);
Expect(29);
break;
}
case 30: {
Get();
Expression(out g);
Expect(31);
Graph.MakeOption(g);
break;
}
case 32: {
Get();
Expression(out g);
Expect(33);
Graph.MakeIteration(g);
break;
}
case 38: {
SemText(out pos);
Node p = new Node(Node.sem, null, 0);
p.pos = pos;
g = new Graph(p);
break;
}
case 23: {
Get();
Node p = new Node(Node.any, null, 0); // p.set is set in Tab.SetupAnys
g = new Graph(p);
break;
}
case 34: {
Get();
Node p = new Node(Node.sync, null, 0);
g = new Graph(p);
break;
}
default: SynErr(53); break;
}
}
void TokenDecl(int typ)
{
string name; int kind; Symbol sym; Graph g;
Sym(out name, out kind);
sym = tab.FindSym(name);
if (sym != null)
{
SemErr("name declared twice");
}
else
{
sym = tab.NewSym(typ, name, t.line);
sym.tokenKind = Symbol.fixedToken;
}
tokenString = null;
while (!(StartOf(5)))
{
SynErr(43); Get();
}
if (la.kind == 17)
{
Get();
TokenExpr(out g);
Expect(18);
if (kind == str)
{
SemErr("a literal must not be declared with a structure");
}
tab.Finish(g);
if (tokenString == null || tokenString.Equals(noString))
{
dfa.ConvertToStates(g.l, sym);
}
else // TokenExpr is a single string
{
if (tab.literals[tokenString] != null)
{
SemErr("token string declared twice");
}
tab.literals[tokenString] = sym;
dfa.MatchLiteral(tokenString, sym);
}
}
else if (StartOf(6))
{
if (kind == id)
{
genScanner = false;
}
else
{
dfa.MatchLiteral(sym.name, sym);
}
}
else
{
SynErr(44);
}
if (la.kind == 39)
{
SemText(out sym.semPos);
if (typ != Node.pr)
{
SemErr("semantic action not allowed here");
}
}
}
static void TokenDecl(int typ)
{
string name; int kind; Symbol sym; Graph g;
Sym(out name, out kind);
sym = Symbol.Find(name);
if (sym != null)
{
SemErr("name declared twice");
}
else
{
sym = new Symbol(typ, name, t.line);
sym.tokenKind = Symbol.classToken;
}
while (!(StartOf(13)))
{
SynErr(46); Get();
}
if (la.kind == 8)
{
Get();
TokenExpr(out g);
Expect(9);
if (kind != id)
{
SemErr("a literal must not be declared with a structure");
}
Graph.Finish(g);
DFA.ConvertToStates(g.l, sym);
}
else if (la.kind == 9)
{
Get();
if (typ != Node.rslv)
{
SemErr("resolver is only allowed in RESOLVERS section");
}
}
else if (StartOf(14))
{
if (kind == id)
{
genScanner = false;
}
else
{
DFA.MatchLiteral(sym);
}
}
else
{
SynErr(47);
}
if (la.kind == 38)
{
SemText(out sym.semPos);
if (typ == Node.t)
{
SemErr("semantic action not allowed here");
}
}
else if (StartOf(15))
{
if (typ == Node.rslv)
{
SemErr("resolvers must have a semantic action");
}
}
else
{
SynErr(48);
}
}