/** implements Tomita's Graph Structured Stack */
class GSS {
+ public static int count = 0;
public GSS() { }
private Phase.Node[] reducing_list = null;
public Forest.Ref finalResult;
/** corresponds to a positions <i>between tokens</i> the input stream; same as Tomita's U_i's */
- public class Phase<Tok> implements Invokable<State, Forest, Phase<Tok>.Node>, IntegerMappable {
+ class Phase<Tok> implements Invokable<State, Forest, Phase<Tok>.Node>, IntegerMappable {
public void invoke(State st, Forest result, Node n) {
good |= next.newNode(n, result, st, false);
private Forest forest;
- public Phase(Phase prev, Parser parser, Phase previous, Tok token, Input.Location location, Forest forest) {
+ public Phase(Phase prev, Parser parser, Phase previous, Tok token, Input.Location location, Forest forest) throws ParseFailed {
this.prev = prev;
this.forest = forest;
this.parser = parser;
reset();
}
- public void reset() {
+ public void reset() throws ParseFailed {
waiting.clear();
performed.clear();
hash = new IntPairMap<Phase.Node>();
singularReductions = new IntPairMap<Forest>();
expectedInhibit.clear();
expectedInhibit.addAll(inhibited);
+ reset = false;
good = false;
closed = false;
reducing = false;
}
if (!owner.lame)
newNode(parent, pending, state, fromEmptyReduction);
- if (reduction!=null) inhibit(reduction, parent==null?0:parent.phase().pos);
+ if (reduction!=null) uninhibit(reduction, parent==null?0:parent.phase().pos);
if (reduction != null) {
boolean redo = true;
while(redo) {
return true;
}
- public void uninhibit(int p, Sequence s) {
+ public void inhibit(int p, Sequence s) {
if (s.hated!=null)
for(Sequence s2 : s.hated)
inhibited.remove(p, s2);
}
- public void inhibit(Position r, int p) {
+ public void uninhibit(Position r, int p) {
if (r.owner().hated == null) return;
// remember that dead states are still allowed to shift -- just not allowed to reduce
boolean reset = false;
for(Sequence seq : r.owner().hated) {
if (performed.contains(p,seq)) {
- uninhibit(p, seq);
+ inhibit(p, seq);
//System.out.println("\nresetting due to " + r.owner() + " killing " + seq);
//inhibited.clear();
inhibited.add(p, seq);
}
/** perform all reduction operations */
- public void reduce() {
+ public void reduce() throws ParseFailed{
try {
reducing = true;
if (reducing_list==null || reducing_list.length < hash.size())
reset();
reduce();
}
+ count = 0;
}
+ private boolean reset = false;
class Reset extends RuntimeException { }
/** perform all shift operations, adding promoted nodes to <tt>next</tt> */
}
if (!good && token!=null)
- throw new ParseFailed(ParseFailed.error(ANSI.red("unexpected character")+" "+ANSI.purple(token)+" encountered at "+ANSI.green(getLocation())+"\n", token, hash.values()),
+ throw new ParseFailed(ParseFailed.error(ANSI.red("unexpected character ")+" \'"+
+ ANSI.purple(StringUtil.escapify(token+"", "\\\'\r\n"))+
+ "\' encountered at "+
+ ANSI.green(getLocation())+"\n", token, hash.values()),
getLocation());
if (token==null && finalResult==null)
throw new ParseFailed(ParseFailed.error(ANSI.red("unexpected end of file\n"), token, hash.values()),
}
- public class Waiting {
+ class Waiting {
Node parent;
Forest pending;
State state;
// Node /////////////////////////////////////////////////////////////////////////////////
/** a node in the GSS */
- public final class Node extends FastSet<Node> implements Invokable<Position, Node, Node>, IntegerMappable {
+ final class Node extends FastSet<Node> implements Invokable<Position, Node, Node>, IntegerMappable {
private Forest.Ref holder = null;
private boolean allqueued = false;
else state.invokeReductions(token, this, this, n2);
}
+ public void performEmptyReductions() { state.invokeReductions(token, this, null, null); }
public final void invoke(Position r, Node n, Node n2) {
if (n==null || n2==null || r.pos==0) {
if (r.pos==0) {
Forest[] holder = new Forest[r.pos];
if (r.pos<=0) throw new Error("called wrong form of reduce()");
int pos = r.pos-1;
- Forest old = holder[pos];
- holder[pos] = n.pending();
- if (pos==0) {
- System.arraycopy(holder, 0, r.holder, 0, holder.length);
- Forest rex = null;
- if (r.pos==1) rex = singularReductions.get(this, r);
- if (rex==null) {
- rex = r.rewrite(n.phase().getLocation());
- if (r.pos==1) singularReductions.put(this, r, rex);
- }
- n2.finish(r, rex, n.phase(), holder);
- } else {
- n2.reduce(r, pos-1, n.phase(), holder);
- }
- holder[pos] = old;
+ n.reduce(r, pos, n.phase(), holder, n2);
}
}
- public void reduce(Position r, int pos, Phase target, Forest[] holder) {
+ public void reduce(Position r, int pos, Phase target, Forest[] holder) { reduce(r, pos, target, holder, null); }
+ public void reduce(Position r, int pos, Phase target, Forest[] holder, Node only) {
Forest old = holder[pos];
holder[pos] = this.pending();
if (pos==0) {
System.arraycopy(holder, 0, r.holder, 0, holder.length);
for(int i=0; i<r.pos; i++) if (r.holder[i]==null) throw new Error("realbad");
Forest rex = null;
- if (r.pos==1) rex = singularReductions.get(this, r);
+
+ // FIXME: I'm unsure about this -- basically we want to deal with the case where
+ // there are two nodes, each of whose Ref points to the same Forest instance.
+ // Some node in the next phase has both of these as parents. This might happen
+ // since the same reduction can appear in more than one state.
+ if (r.pos==1) rex = singularReductions.get(this.pending(), r);
if (rex==null) {
rex = r.rewrite(phase().getLocation());
- if (r.pos==1) singularReductions.put(this, r, rex);
+ if (r.pos==1) singularReductions.put(this.pending(), r, rex);
}
- for(Node child : this.parents()) child.finish(r, rex, target, holder);
+ if (only != null) only.finish(r, rex, target, holder);
+ else for(Node child : this.parents()) child.finish(r, rex, target, holder);
} else {
- for(Node child : this.parents()) child.reduce(r, pos-1, target, holder);
+ if (only != null) only.reduce(r, pos-1, target, holder);
+ else for(Node child : this.parents()) child.reduce(r, pos-1, target, holder);
}
holder[pos] = old;
}
target.newNode(this, result, state0, r.pos<=0, r);
}
- public void performEmptyReductions() { state.invokeReductions(token, this, null, null); }
-
private Node(Node parent, Forest pending, State state) {
this.state = state;
this.holder().merge(pending);
projects / sbp.git / blobdiff