import java.lang.reflect.*;
/** an efficient representation of a collection of trees (Tomita's shared packed parse forest) */
-public abstract class Forest<T> /*extends PrintableTree<Forest.Body<T>>*/ implements Visitable<Forest.Body<T>> {
-
- public abstract <B,C> void invoke(Invokable<Forest.Body<T>,B,C> ivbc, B b, C c);
- private static class TreeMaker<T> extends HashSet<Tree<T>> implements Invokable<Forest.Body<T>,Boolean,Integer> {
- public ArrayList<Tree<T>> toks = new ArrayList<Tree<T>>();
- public void invoke(Forest.Body<T> bod, Boolean toss, Integer i) {
- if (i==null) {
- addAll(bod.expand(toss, 0, new TreeMaker<T>()));
- } else {
- bod.expand(toss, i, this);
- }
- }
- }
+public abstract class Forest<T> /*extends PrintableTree<Forest.MyBody<T>>*/ implements Visitable<Forest.Body<T>> {
/** assume that this forest contains exactly one tree and return it; otherwise throw an exception */
public final Tree<T> expand1() throws Ambiguous, ParseFailed {
/** expand this forest into a set of trees */
public HashSet<Tree<T>> expand(boolean toss) {
- TreeMaker<T> ret = new TreeMaker<T>();
- invoke(ret, new Boolean(toss), null);
- if (toss && ret.size() > 1) throw new Ambiguous(this);
- return ret;
+ final HashSet<Tree<T>> hs = new HashSet<Tree<T>>();
+ TreeMaker<T> ret = new TreeMaker<T>(toss) {
+ public void start(T head, Input.Location loc) { }
+ public void finish(T head, Input.Location loc) { hs.add(new Tree<T>(loc, head, toks.toArray(tree_hint))); }
+ public void child(Tree<T> t) { toks.add(t); }
+ };
+ visit(ret, null, null);
+ if (toss && hs.size() > 1) throw new Ambiguous(this);
+ return hs;
}
static <T> Forest<T> singleton(Input.Location loc) { return create(loc, null, new Forest[] { }, false, true); }
// Body //////////////////////////////////////////////////////////////////////////////
protected static interface Body<T> {
- TreeMaker<T> expand(boolean toss, int i, TreeMaker<T> h);
+ TreeMaker<T> expand(int i, TreeMaker<T> h);
}
protected static class MyBody<T> extends Forest<T> implements Body<T> /* extends PrintableTree<Forest<T>> implements */ {
- public <B,C> void invoke(Invokable<Forest.Body<T>,B,C> ivbc, B b, C c) {
+ public <B,C> void visit(Invokable<Forest.Body<T>,B,C> ivbc, B b, C c) {
ivbc.invoke(this, b, c);
}
- public Iterator<Body<T>> iterator() { return new SingletonIterator<Body<T>>(this); }
private final Input.Location location;
private final T tag;
this.singleton = singleton;
}
- public TreeMaker<T> expand(boolean toss, int i, TreeMaker<T> h) {
+ public TreeMaker<T> expand(final int i, final TreeMaker<T> h) {
if (singleton) {
- tokens[0].invoke(h, toss, i);
+ tokens[0].visit(h, null, i);
+ return h;
+ }
+ if (i==0) h.start(tag, location);
- } else if (i==tokens.length) {
- h.add(new Tree<T>(null, tag, h.toks.toArray(tree_hint)));
+ if (i==tokens.length) {
+ h.finish(tag, location);
} else if (unwrap && i==tokens.length-1) {
if (tokens[i] != null)
- tokens[i].invoke(h, toss, 0);
+ tokens[i].visit(h, null, 0);
} else {
- boolean hit = false;
- for(Tree<T> r : tokens[i].expand(toss)) {
- hit = true;
- int old = h.toks.size();
- h.toks.add(r);
- expand(toss, i+1, h);
- while(h.toks.size() > old) h.toks.remove(h.toks.size()-1);
- }
- //if (!hit) throw new Error();
+ tokens[i].visit(new TreeMaker<T>(h.toss) {
+ public void start(T head, Input.Location loc) { }
+ public void child(Tree<T> t) { toks.add(t); }
+ public void finish(T head, Input.Location loc) {
+ int old = h.toks.size();
+ h.child(new Tree<T>(loc, head, toks.toArray(tree_hint)));
+ expand(i+1, h);
+ while(h.toks.size() > old) h.toks.remove(h.toks.size()-1);
+ }
+ }, null, null);
}
return h;
}
private FastSet<Forest<T>> hp = new FastSet<Forest<T>>();
public Ref() { }
public void merge(Forest p) { if (p!=this) hp.add(p, true); }
- public <B,C> void invoke(Invokable<Forest.Body<T>,B,C> ivbc, B b, C c) {
+ public <B,C> void visit(Invokable<Forest.Body<T>,B,C> ivbc, B b, C c) {
if (hp==null) return;
- for(Forest<T> f : hp) f.invoke(ivbc, b, c);
+ for(Forest<T> f : hp)
+ f.visit(ivbc, b, c);
}
public Forest resolve() { return this; }
}
+ public abstract <B,C> void visit(Invokable<Forest.Body<T>,B,C> ivbc, B b, C c);
+ private static abstract class TreeMaker<T> implements Invokable<Forest.Body<T>,Boolean,Integer> {
+ public ArrayList<Tree<T>> toks = new ArrayList<Tree<T>>();
+ private boolean toss;
+ protected T head;
+ public TreeMaker(boolean toss) { this.toss = toss; }
+ public abstract void start(T head, Input.Location loc);
+ public abstract void finish(T head, Input.Location loc);
+ public abstract void child(Tree<T> t);
+ public void invoke(Forest.Body<T> bod, Boolean o, Integer i) {
+ if (i==null) {
+ ArrayList<Tree<T>> toks = this.toks;
+ this.toks = new ArrayList<Tree<T>>();
+ bod.expand(0, this);
+ this.toks = toks;
+ } else {
+ bod.expand(i, this);
+ }
+ }
+ }
// Statics //////////////////////////////////////////////////////////////////////////////
projects / sbp.git / blobdiff