+// Copyright 2006 all rights reserved; see LICENSE file for BSD-style license
+
package edu.berkeley.sbp;
import edu.berkeley.sbp.*;
import edu.berkeley.sbp.util.*;
import java.io.*;
import java.util.*;
-/** a parser which translates streams of Tokens of type T into a Forest<R> */
-public abstract class Parser<T extends Token, R> {
+/** a parser which translates an Input<Token> into a Forest<NodeType> */
+public abstract class Parser<Token, NodeType> {
- private final Table pt;
+ protected final Table<Token> pt;
/** create a parser to parse the grammar with start symbol <tt>u</tt> */
- protected Parser(Union u) { this.pt = new Table(u, top()); }
- //protected Parser(Table pt) { this.pt = pt; }
+ public Parser(Union u, Topology<Token> top) { this.pt = new Table<Token>(u, top); }
/** implement this method to create the output forest corresponding to a lone shifted input token */
- public abstract Forest<R> shiftedToken(T t, Token.Location loc);
-
- /** this method must return an empty topology of the input token type */
- public abstract Topology<T> top();
-
- /** parse <tt>input</tt> for a exactly one unique result, throwing <tt>Ambiguous</tt> if not unique or <tt>ParseFailed</tt> if none */
- public Tree<R> parse1(Token.Stream<T> input) throws IOException, ParseFailed, Ambiguous {
- Forest<R> ret = parse(input);
- try { return ret.expand1(); }
- catch (Ambiguous a) {
- System.out.println("while expanding:");
- System.out.println(ret);
- throw a;
+ public abstract Forest<NodeType> shiftToken(Token t, Input.Location newloc);
+
+ public String toString() { return pt.toString(); }
+
+ private boolean verbose = false;;
+ private static final char[] spin = new char[] { '-', '\\', '|', '/' };
+ private int spinpos = 0;
+ private long last = 0;
+ void spin() {
+ if (verbose) {
+ long now = System.currentTimeMillis();
+ if (now-last < 70) return;
+ last = now;
+ System.err.print("\r " + spin[spinpos++ % (spin.length)]+"\r");
}
}
- /** parse <tt>input</tt>, using the table <tt>pt</tt> to drive the parser */
- public Forest<R> parse(Token.Stream<T> input) throws IOException, ParseFailed {
- GSS gss = new GSS();
- Token.Location loc = input.getLocation();
- GSS.Phase current = gss.new Phase(null, this, null, input.next(1, 0, 0), loc, null);
- current.newNode(null, Forest.leaf(null, null), pt.start, true);
- int count = 1;
- for(;;) {
- loc = input.getLocation();
- current.reduce();
- Forest forest = current.token==null ? null : shiftedToken((T)current.token, loc);
- GSS.Phase next = gss.new Phase(current, this, current, input.next(count, gss.resets, gss.waits), loc, forest);
- count = next.hash.size();
- if (current.isDone()) return (Forest<R>)current.finalResult;
- current = next;
+ /** parse <tt>input</tt>, and return the shared packed parse forest (or throw an exception) */
+ public Forest<NodeType> parse(Input<Token> input) throws IOException, ParseFailed {
+ verbose = System.getProperty("sbp.verbose", null) != null;
+ spinpos = 0;
+ try {
+ GSS gss = new GSS(input, this);
+ for(GSS.Phase current = gss.new Phase<Token>(pt.start); ;) {
+
+ if (verbose) {
+ String s;
+ s = " " + spin[spinpos++ % (spin.length)]+" parsing ";
+ s += input.getName();
+ s += " "+input.getLocation();
+ while(s.indexOf(':') != -1 && s.indexOf(':') < 8) s = " " + s;
+ String y = "@"+gss.viewPos+" ";
+ while(y.length() < 9) y = " " + y;
+ s += y;
+ //s += " doom="+Node.doomedNodes;
+ //while(s.length() < 40) s = s + " ";
+ s += " nodes="+gss.numOldNodes;
+ while(s.length() < 50) s = s + " ";
+ s += " shifted="+gss.numNewNodes;
+ while(s.length() < 60) s = s + " ";
+ s += " reductions="+gss.numReductions;
+ System.err.print("\r"+s+ANSI.clreol()+"\r");
+ }
+
+ // FIXME: make sure all the locations line up properly in here
+ if (current.isDone()) return (Forest<NodeType>)current.finalResult;
+ Forest forest = shiftToken((Token)current.token, input.getLocation());
+ current = gss.new Phase<Token>(current, forest);
+ }
+ } finally {
+ if (verbose)
+ System.err.print("\r \r");
}
}
-
-
- // Exceptions //////////////////////////////////////////////////////////////////////////////
// Table //////////////////////////////////////////////////////////////////////////////
/** an SLR(1) parse table which may contain conflicts */
- static class Table extends Walk.Cache {
-
- public final Walk.Cache cache = this;
-
- public HashMapBag<Position,State> byPosition = new HashMapBag<Position,State>();
-
- private void walk(Element e, HashSet<Element> hs) {
- if (e==null) return;
- if (hs.contains(e)) return;
- hs.add(e);
- if (e instanceof Atom) return;
- for(Sequence s : (Union)e) {
- hs.add(s);
- for(Position p = s.firstp(); p != null; p = p.next())
- walk(p.element(), hs);
- }
- }
+ static class Table<Token> extends Cache {
/** the start state */
- public final State start;
+ public final State<Token> start;
+
+ /** the state from which no reductions can be done */
+ private final State<Token> dead_state;
/** used to generate unique values for State.idx */
private int master_state_idx = 0;
+ HashSet<State<Token>> all_states = new HashSet<State<Token>>();
+ HashMap<HashSet<Position>,State<Token>> doomed_states = new HashMap<HashSet<Position>,State<Token>>();
+ HashMap<HashSet<Position>,State<Token>> normal_states = new HashMap<HashSet<Position>,State<Token>>();
/** construct a parse table for the given grammar */
public Table(Topology top) { this("s", top); }
public Table(String startSymbol, Topology top) { this(new Union(startSymbol), top); }
public Table(Union ux, Topology top) {
+ super(ux, top);
Union start0 = new Union("0");
- start0.add(new Sequence.Singleton(ux, null, null));
-
- for(Sequence s : start0) cache.eof.put(s, true);
- cache.eof.put(start0, true);
+ Sequence seq0 = new Sequence.Singleton(ux);
+ start0.add(seq0);
+ buildFollowSet(seq0, top, true);
// construct the set of states
- HashMap<HashSet<Position>,State> all_states = new HashMap<HashSet<Position>,State>();
- HashSet<Element> all_elements = new HashSet<Element>();
- walk(start0, all_elements);
- for(Element e : all_elements)
- cache.ys.put(e, new Walk.YieldSet(e, cache).walk());
HashSet<Position> hp = new HashSet<Position>();
reachable(start0, hp);
- this.start = new State(hp, all_states, all_elements);
+
+ this.dead_state = new State<Token>(new HashSet<Position>(), true);
+ this.start = new State<Token>(hp);
// for each state, fill in the corresponding "row" of the parse table
- for(State state : all_states.values())
+ for(State<Token> state : all_states)
for(Position p : state.hs) {
// the Grammar's designated "last position" is the only accepting state
- if (start0.contains(p.owner()) && p.next()==null)
+ if (start0.contains(p.owner()) && p.next()==null && !state.doomed)
state.accept = true;
- if (p.isRightNullable(cache)) {
- Walk.Follow wf = new Walk.Follow(top.empty(), p.owner(), all_elements, cache);
- Reduction red = new Reduction(p);
-
- Topology follow = wf.walk(p.owner());
- if (p.owner() instanceof Sequence.RewritingSequence &&
- (((Sequence.RewritingSequence)p.owner()).tag+"").equals("emailaddr")) {
- System.out.println("follow before: " + new edu.berkeley.sbp.misc.CharToken.CharRange(follow));
+ if (isRightNullable(p)) {
+ Topology<Token> follow = (Topology<Token>)follow(p.owner());
+ for(Position p2 = p; p2 != null && p2.element() != null; p2 = p2.next()) {
+ if (!(p2.element() instanceof Union)) throw new Error("impossible");
+ Union u = (Union)p2.element();
+ Atom set = new edu.berkeley.sbp.chr.CharAtom(new edu.berkeley.sbp.chr.CharTopology((Topology<Character>)epsilonFollowSet(u)));
+ Element p2e = p2.element();
+ if (p2e instanceof Union)
+ for(Sequence p2es : ((Union)p2e))
+ follow = follow.intersect(follow(p2es));
+ if (set != null) follow = follow.intersect(set.getTokenTopology());
}
- for(Position p2 = p; p2 != null && p2.element() != null; p2 = p2.next())
- follow = follow.intersect(new Walk.Follow(top.empty(), p2.element(), all_elements, cache).walk(p2.element()));
- if (p.owner() instanceof Sequence.RewritingSequence &&
- (((Sequence.RewritingSequence)p.owner()).tag+"").equals("emailaddr")) {
- System.out.println("follow after: " + new edu.berkeley.sbp.misc.CharToken.CharRange(follow));
- }
- state.reductions.put(follow, red);
- if (wf.includesEof()) state.eofReductions.add(red);
+ state.reductions.put(follow, p);
+ if (followEof.contains(p.owner())) state.eofReductions.add(p);
}
// if the element following this position is an atom, copy the corresponding
// set of rows out of the "master" goto table and into this state's shift table
if (p.element() != null && p.element() instanceof Atom)
- state.shifts.addAll(state.gotoSetTerminals.subset(((Atom)p.element())));
+ state.shifts.addAll(state.gotoSetTerminals.subset(((Atom)p.element()).getTokenTopology()));
}
- for(State state : all_states.values()) {
- state.oreductions = state.reductions.optimize();
- state.oshifts = state.shifts.optimize();
- }
- }
- /** a single state in the LR table and the transitions possible from it */
-
- public class State implements Comparable<Table.State>, IntegerMappable, Iterable<Position> {
-
- public int toInt() { return idx; }
+ if (top instanceof IntegerTopology)
+ for(State<Token> state : all_states) {
+ state.oreductions = state.reductions.optimize(((IntegerTopology)top).functor());
+ state.oshifts = state.shifts.optimize(((IntegerTopology)top).functor());
+ }
- public boolean lame() {
- for(Position p : this)
- for(Position p2 = p; p2!=null; p2=p2.next())
- if (p2.isLast() && !p2.owner().lame)
- return false;
- return true;
- }
- /*
- public boolean isResolvable(Token t) {
- boolean found = false;
- for(Reduction r : getReductions(t)) {
- Position p = r.position;
- if (!p.isRightNullable(cache)) continue;
- if (p.owner().firstp()==p) continue;
- if (found) {
- // found two items meeting criteria #1
- return false;
- } else {
- found = true;
- continue;
+ // crude algorithm to assing an ordinal ordering to every position
+ // al will be sorted in DECREASING order (al[0] >= al[1])
+ ArrayList<Sequence.Position> al = new ArrayList<Sequence.Position>();
+ for(State s : all_states) {
+ for(Object po : s) {
+ Sequence.Position p = (Sequence.Position)po;
+ if (al.contains(p)) continue;
+ int i=0;
+ for(; i<al.size(); i++) {
+ if (comparePositions(p, al.get(i)) < 0)
+ break;
}
- if (p.element()==null) continue;
- Topology first = new Walk.First(top(), cache).walk(p.element());
- if (first.contains(t))
+ al.add(i, p);
}
}
+ // FIXME: this actually pollutes the "pure" objects (the ones that should not be modified by the Parser)
+ // sort in increasing order...
+ OUTER: while(true) {
+ for(int i=0; i<al.size(); i++)
+ for(int j=i+1; j<al.size(); j++)
+ if (comparePositions(al.get(i), al.get(j)) > 0) {
+ Sequence.Position p = al.remove(j);
+ al.add(i, p);
+ continue OUTER;
+ }
+ break;
+ }
+
+ int j = 1;
+ int pk = 0;
+ for(int i=0; i<al.size(); i++) {
+ boolean inc = false;
+ for(int k=pk; k<i; k++) {
+ if (comparePositions(al.get(k), al.get(i)) > 0)
+ { inc = true; break; }
+ }
+ inc = true;
+ if (inc) {
+ j++;
+ pk = i;
+ }
+ al.get(i).ord = j;
+ }
+
+ /*
+ for(int i=0; i<al.size(); i++)
+ if (isRightNullable(al.get(i)))
+ System.out.println(al.get(i).ord + " " + al.get(i));
*/
+ //mastercache = this;
+ }
+ /** a single state in the LR table and the transitions possible from it */
+ class State<Token> implements IntegerMappable, Iterable<Position> {
+
public final int idx = master_state_idx++;
private final HashSet<Position> hs;
+ public HashSet<State<Token>> also = new HashSet<State<Token>>();
- private transient HashMap<Element,State> gotoSetNonTerminals = new HashMap<Element,State>();
- private transient TopologicalBag<Token,State> gotoSetTerminals = new TopologicalBag<Token,State>();
+ public transient HashMap<Sequence,State<Token>> gotoSetNonTerminals = new HashMap<Sequence,State<Token>>();
+ private transient TopologicalBag<Token,State<Token>> gotoSetTerminals = new TopologicalBag<Token,State<Token>>();
- private TopologicalBag<Token,Reduction> reductions = new TopologicalBag<Token,Reduction>();
- private HashSet<Reduction> eofReductions = new HashSet<Reduction>();
- private TopologicalBag<Token,State> shifts = new TopologicalBag<Token,State>();
- private boolean accept = false;
+ private TopologicalBag<Token,Position> reductions = new TopologicalBag<Token,Position>();
+ private HashSet<Position> eofReductions = new HashSet<Position>();
+ private TopologicalBag<Token,State<Token>> shifts = new TopologicalBag<Token,State<Token>>();
+ private boolean accept = false;
- private VisitableMap<Token,State> oshifts = null;
- private VisitableMap<Token,Reduction> oreductions = null;
+ private VisitableMap<Token,State<Token>> oshifts = null;
+ private VisitableMap<Token,Position> oreductions = null;
// Interface Methods //////////////////////////////////////////////////////////////////////////////
- public boolean isAccepting() { return accept; }
-
- public boolean canShift(Token t) { return oshifts.contains(t); }
- public boolean canReduce(Token t) { return t==null ? eofReductions.size()>0 : oreductions.contains(t); }
-
- public Iterator<Position> iterator() { return hs.iterator(); }
-
- public <B,C> void invokeShifts(Token t, Invokable<State,B,C> irbc, B b, C c) {
- oshifts.invoke(t, irbc, b, c);
+ boolean isAccepting() { return accept; }
+ public Iterator<Position> iterator() { return hs.iterator(); }
+ boolean canShift(Token t) { return oshifts!=null && oshifts.contains(t); }
+ void invokeShifts(Token t, GSS.Phase phase, Result r) { oshifts.invoke(t, phase, r); }
+ boolean canReduce(Token t) {
+ return oreductions != null && (t==null ? eofReductions.size()>0 : oreductions.contains(t)); }
+ void invokeEpsilonReductions(Token t, Node node) {
+ if (t==null) for(Position r : eofReductions) node.invoke(r, null);
+ else oreductions.invoke(t, node, null);
}
- public <B,C> void invokeReductions(Token t, Invokable<Reduction,B,C> irbc, B b, C c) {
- if (t==null) for(Reduction r : eofReductions) irbc.invoke(r, b, c);
- else oreductions.invoke(t, irbc, b, c);
+ void invokeReductions(Token t, Node node, Result b) {
+ //System.err.println("\rinvokage: " + this);
+ if (t==null) for(Position r : eofReductions) node.invoke(r, b);
+ else oreductions.invoke(t, node, b);
}
// Constructor //////////////////////////////////////////////////////////////////////////////
/**
* create a new state consisting of all the <tt>Position</tt>s in <tt>hs</tt>
* @param hs the set of <tt>Position</tt>s comprising this <tt>State</tt>
- * @param all_states the set of states already constructed (to avoid recreating states)
- * @param all_elements the set of all elements (Atom instances need not be included)
+ * @param all the set of all elements (Atom instances need not be included)
*
* In principle these two steps could be merged, but they
* are written separately to highlight these two facts:
* for non-Atom Elements.
* </ul>
*/
- public State(HashSet<Position> hs,
- HashMap<HashSet<Position>,State> all_states,
- HashSet<Element> all_elements) {
+ public State(HashSet<Position> hs) { this(hs, false); }
+ public boolean doomed;
+ public State(HashSet<Position> hs, boolean doomed) {
this.hs = hs;
+ this.doomed = doomed;
// register ourselves in the all_states hash so that no
// two states are ever created with an identical position set
- all_states.put(hs, this);
- for(Position p : hs) byPosition.add(p,this);
+ ((HashMap)(doomed ? doomed_states : normal_states)).put(hs, this);
+ ((HashSet)all_states).add(this);
+
+ for(Position p : hs) {
+ if (!p.isFirst()) continue;
+ for(Sequence s : p.owner().needs()) {
+ if (hs.contains(s.firstp())) continue;
+ HashSet<Position> h2 = new HashSet<Position>();
+ reachable(s, h2);
+ also.add(mkstate(h2, true));
+ }
+ for(Sequence s : p.owner().hates()) {
+ if (hs.contains(s.firstp())) continue;
+ HashSet<Position> h2 = new HashSet<Position>();
+ reachable(s, h2);
+ also.add(mkstate(h2, true));
+ }
+ }
// Step 1a: examine all Position's in this state and compute the mappings from
// sets of follow tokens (tokens which could follow this position) to sets
Atom a = (Atom)position.element();
HashSet<Position> hp = new HashSet<Position>();
reachable(position.next(), hp);
- bag0.addAll(a, hp);
+ bag0.addAll(a.getTokenTopology(), hp);
}
// Step 1b: for each _minimal, contiguous_ set of characters having an identical next-position
for(Topology<Token> r : bag0) {
HashSet<Position> h = new HashSet<Position>();
for(Position p : bag0.getAll(r)) h.add(p);
- gotoSetTerminals.put(r, all_states.get(h) == null ? new State(h, all_states, all_elements) : all_states.get(h));
+ ((TopologicalBag)gotoSetTerminals).put(r, mkstate(h, doomed));
}
- // Step 2: for every non-Atom element (ie every Element which has a corresponding reduction),
- // compute the closure over every position in this set which is followed by a symbol
- // which could yield the Element in question.
+ // Step 2: for every Sequence, compute the closure over every position in this set which
+ // is followed by a symbol which could yield the Sequence.
//
// "yields" [in one or more step] is used instead of "produces" [in exactly one step]
// to avoid having to iteratively construct our set of States as shown in most
// expositions of the algorithm (ie "keep doing XYZ until things stop changing").
- /*
- for(Element e : all_elements) {
- if (e instanceof Atom) continue;
- HashSet<Position> h = new Walk.Closure(null, g.cache).closure(e, hs);
- State s = all_states.get(h) == null ? new State(h, all_states, all_elements) : all_states.get(h);
- if (gotoSetNonTerminals.get(e) != null)
- throw new Error("this should not happen");
- gotoSetNonTerminals.put(e, s);
- }
- */
- HashMapBag<Element,Position> move = new HashMapBag<Element,Position>();
- for(Position p : hs) {
- Element e = p.element();
- if (e==null) continue;
- HashSet<Element> ys = cache.ys.get(e);
- if (ys != null) {
- for(Element y : ys) {
+
+ HashMapBag<Sequence,Position> move = new HashMapBag<Sequence,Position>();
+ for(Position p : hs)
+ if (!p.isLast() && p.element() instanceof Union)
+ for(Sequence s : ((Union)p.element())) {
HashSet<Position> hp = new HashSet<Position>();
reachable(p.next(), hp);
- move.addAll(y, hp);
+ move.addAll(s, hp);
}
- }
- }
- for(Element y : move) {
+ OUTER: for(Sequence y : move) {
+ // if a reduction is "lame", it should wind up in the dead_state after reducing
HashSet<Position> h = move.getAll(y);
- State s = all_states.get(h) == null ? new State(h, all_states, all_elements) : all_states.get(h);
+ State<Token> s = mkstate(h, doomed);
+ for(Position p : hs)
+ if (p.element() != null && (p.element() instanceof Union))
+ for(Sequence seq : ((Union)p.element()))
+ if (seq.needs.contains(y) || seq.hates.contains(y)) {
+ // FIXME: assumption that no sequence is ever both usefully (non-lamely) matched
+ // and also directly lamely matched
+ ((HashMap)gotoSetNonTerminals).put(y, dead_state);
+ continue OUTER;
+ }
gotoSetNonTerminals.put(y, s);
}
}
+ private State<Token> mkstate(HashSet<Position> h, boolean b) {
+ if (b) return doomed_states.get(h) == null ? (State)new State<Token>(h,b) : (State)doomed_states.get(h);
+ else return normal_states.get(h) == null ? (State)new State<Token>(h,b) : (State)normal_states.get(h);
+ }
+
+ public String toStringx() {
+ StringBuffer st = new StringBuffer();
+ for(Position p : this) {
+ if (st.length() > 0) st.append("\n");
+ st.append(p);
+ }
+ return st.toString();
+ }
+
public String toString() {
- //return "state["+idx+"]";
StringBuffer ret = new StringBuffer();
ret.append("state["+idx+"]: ");
for(Position p : this) ret.append("{"+p+"} ");
return ret.toString();
}
- public int compareTo(Table.State s) { return idx==s.idx ? 0 : idx < s.idx ? -1 : 1; }
+ public int toInt() { return idx; }
}
- /**
- * the information needed to perform a reduction; copied here to
- * avoid keeping references to <tt>Element</tt> objects in a Table
- */
- public class Reduction {
- // FIXME: cleanup; almost everything in here could go in either Sequence.Position.getRewrite() or else in GSS.Reduct
- public final int numPop;
- /*private*/ final Position position;
- private final Forest[] holder; // to avoid constant reallocation
- public int hashCode() { return position.hashCode(); }
- public boolean equals(Object o) {
- if (o==null) return false;
- if (o==this) return true;
- if (!(o instanceof Reduction)) return false;
- Reduction r = (Reduction)o;
- return r.position == position;
- }
- public Reduction(Position p) {
- this.position = p;
- this.numPop = p.pos;
- this.holder = new Forest[numPop];
- }
- public String toString() { return "[reduce " + position + "]"; }
-
- private Forest zero = null;
- public Forest zero() {
- if (zero != null) return zero;
- if (numPop > 0) throw new Error();
- return zero = position.rewrite(null);
- }
-
- public void reduce(GSS.Phase.Node parent) {
- if (numPop==0) finish(parent, zero(), parent.phase());
- else reduce(parent, numPop-1, parent.phase());
- }
-
- public void reduce(GSS.Phase.Node parent, GSS.Phase.Node onlychild) {
- if (numPop<=0) throw new Error("called wrong form of reduce()");
- int pos = numPop-1;
- Forest old = holder[pos];
- holder[pos] = parent.pending();
- if (pos==0) {
- System.arraycopy(holder, 0, position.holder, 0, holder.length);
- finish(onlychild, position.rewrite(parent.phase().getLocation()), parent.phase());
- } else {
- reduce(onlychild, pos-1, parent.phase());
+ public String toString() {
+ StringBuffer sb = new StringBuffer();
+ sb.append("parse table");
+ for(State<Token> state : all_states) {
+ sb.append(" " + state + "\n");
+ for(Topology<Token> t : state.shifts) {
+ sb.append(" shift \""+
+ new edu.berkeley.sbp.chr.CharTopology((IntegerTopology<Character>)t)+"\" => ");
+ for(State st : state.shifts.getAll(t))
+ sb.append(st.idx+" ");
+ sb.append("\n");
}
- holder[pos] = old;
- }
-
- // FIXME: this could be more elegant and/or cleaner and/or somewhere else
- private void reduce(GSS.Phase.Node parent, int pos, GSS.Phase target) {
- Forest old = holder[pos];
- holder[pos] = parent.pending();
- if (pos==0) {
- System.arraycopy(holder, 0, position.holder, 0, holder.length);
- for(int i=0; i<position.pos; i++) if (position.holder[i]==null) throw new Error("realbad");
- Forest rex = position.rewrite(target.getLocation());
- for(GSS.Phase.Node child : parent.parents()) finish(child, rex, target);
- } else {
- for(GSS.Phase.Node child : parent.parents()) reduce(child, pos-1, target);
- }
- holder[pos] = old;
- }
- private void finish(GSS.Phase.Node parent, Forest result, GSS.Phase target) {
- State state = parent.state.gotoSetNonTerminals.get(position.owner());
- if (result==null) throw new Error();
- if (state!=null)
- target.newNode(parent, result, state, numPop<=0, this);
+ for(Topology<Token> t : state.reductions)
+ sb.append(" reduce \""+
+ new edu.berkeley.sbp.chr.CharTopology((IntegerTopology<Character>)t)+"\" => " +
+ state.reductions.getAll(t) + "\n");
+ for(Sequence s : state.gotoSetNonTerminals.keySet())
+ sb.append(" goto "+state.gotoSetNonTerminals.get(s)+" from " + s + "\n");
}
+ return sb.toString();
}
}
- private static final Forest[] emptyForestArray = new Forest[0];
-
-
// Helpers //////////////////////////////////////////////////////////////////////////////
-
+
+ private static void reachable(Sequence s, HashSet<Position> h) {
+ reachable(s.firstp(), h);
+ //for(Sequence ss : s.needs()) reachable(ss, h);
+ //for(Sequence ss : s.hates()) reachable(ss, h);
+ }
private static void reachable(Element e, HashSet<Position> h) {
if (e instanceof Atom) return;
for(Sequence s : ((Union)e))
- reachable(s.firstp(), h);
+ reachable(s, h);
}
private static void reachable(Position p, HashSet<Position> h) {
if (h.contains(p)) return;
h.add(p);
if (p.element() != null) reachable(p.element(), h);
}
-
+ //public static Cache mastercache = null;
}
projects / sbp.git / blobdiff