X-Git-Url: http://git.megacz.com/?p=sbp.git;a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2FSequence.java;h=5680d6c5f17ca3cb51eb40af4e03c4177adddf2c;hp=a75bafa008243da5b7f83fd045e8362002e1af5d;hb=2c1c0293545f3d12c23220fd05c663e6aa3f3de1;hpb=6ae224025882c9929e2e4e9e8461decbf3b9cae4 diff --git a/src/edu/berkeley/sbp/Sequence.java b/src/edu/berkeley/sbp/Sequence.java index a75bafa..5680d6c 100644 --- a/src/edu/berkeley/sbp/Sequence.java +++ b/src/edu/berkeley/sbp/Sequence.java @@ -7,64 +7,73 @@ import java.util.*; import java.lang.reflect.*; import java.lang.ref.*; -/** juxtaposition; zero or more adjacent Elements; can specify a rewriting */ -public abstract class Sequence extends Element implements Iterable { +/** juxtaposition; zero or more adjacent Elements; can specify a rewriting */ +public abstract class Sequence implements Iterable, SequenceOrElement { + + protected final Element[] elements; + + final HashSet hated = new HashSet(); + + final HashSet needs = new HashSet(); + final HashSet hates = new HashSet(); + + final Position firstp; + + Atom follow = null; // Static Constructors ////////////////////////////////////////////////////////////////////////////// abstract Sequence _clone(); Sequence dup() { Sequence ret = _clone(); - for(Sequence s : needs) { ret.needs.add(s); s.needed.add(ret); } + for(Sequence s : needs) { ret.needs.add(s); } for(Sequence s : hates) { ret.hates.add(s); s.hated.add(ret); } ret.follow = follow; return ret; } - /** the empty sequence (matches the empty string) */ - public static final Sequence empty = new Sequence.Constant.Empty(); + /** create an empty sequence (matches the empty string) */ + public static Sequence create() { return new Sequence.Constant.Empty(); } - /** after matching the sequence, do not add anything to the output tree */ - public static Sequence drop(Element[] e, boolean lame) { return new Constant.Drop(e, lame); } + /** create a sequence of one element */ + public static Sequence create(Element e) { return create(new Element[] { e }, 0); } - /** after matching the sequence, insert a constant into the output tree */ - public static Sequence constant(Element[] e, Object o) { return new Constant(e, o); } + /** create a sequence which drops the result of all but one of its element */ + public static Sequence create(Element[] e, int which) { return new Singleton(e, which); } - /** after matching the sequence, place the result of the idxth match in the output tree */ - public static Sequence singleton(Element[] e, int idx) { return new Singleton(e, idx); } - public static Sequence singleton(Element e) { return singleton(new Element[] { e }, 0); } + /** create a sequence which always evaluates to a constant result */ + public static Sequence create(Element[] e, Object result) { return new Constant(e, result); } /** - * after matching the sequence, create the specified output tree - * @param tag the tag for the output tree - * @param e the elements to match - * @param drops only elements of e whose corresponding boolean in drops is false will be included in the output tree + * create a sequence (general form) + * @param head the head of the output tree + * @param e the elements to match + * @param drop only elements of e whose corresponding boolean in drops + * is false will be included in the output tree + * @param foster if true, all children of the last child (ie + * grandchildren) are promoted to children of this + * node; this is very useful for matching repetitions **/ - public static Sequence rewritingSequence(Object tag, Element[] e, Object[] labs, boolean[] drops) { - return new RewritingSequence(tag, e, labs, drops); } + public static Sequence create(Object head, Element[] e, boolean[] drop, boolean foster) { + return foster + ? new Unwrap(e, head, drop) + : new RewritingSequence(head, e, drop); + } //////////////////////////////////////////////////////////////////////////////// - public Element follow = null; - public final Topology follow() { return follow==null ? null : Atom.toAtom(follow); } - - Topology toAtom() { - if (elements.length!=1) throw new RuntimeException("cannot invoke toAtom() on a Sequence with " + elements.length + " elements: " + this); - return Atom.toAtom(elements[0]); - } + /** return a new sequence identical to this one, but with a positive conjunct s */ + public Sequence and(Sequence s) { Sequence ret = dup(); ret.needs.add(s); return ret; } - public Sequence and(Sequence s) { Sequence ret = dup(); ret.needs.add(s); s.needed.add(ret); return ret; } - public Sequence not(Sequence s) { Sequence ret = dup(); ret.hates.add(s); s.hated.add(ret); return ret; } + /** return a new sequence identical to this one, but with a negative conjunct s */ + public Sequence andnot(Sequence s) { Sequence ret = dup(); ret.hates.add(s); s.hated.add(ret); return ret; } - protected final Element[] elements; + /** return a new sequence identical to this one, but with a follow-set restricted to a */ + public Sequence followedBy(Atom a) { Sequence ret = dup(); ret.follow = a; return ret; } - final HashSet needed = new HashSet(); - final HashSet hated = new HashSet(); - final HashSet needs = new HashSet(); - final HashSet hates = new HashSet(); - public boolean lame = false; + Iterable needs() { return needs; } + Iterable hates() { return hates; } - final Position firstp; Position firstp() { return firstp; } public Iterator iterator() { return new ArrayIterator(elements); } @@ -74,21 +83,21 @@ public abstract class Sequence extends Element implements Iterable { } // DO NOT MESS WITH THE FOLLOWING LINE!!! - private Forest.Ref epsilonForm = null; + private Forest.Many epsilonForm = null; Forest epsilonForm() { if (epsilonForm!=null) return epsilonForm; - epsilonForm = new Forest.Ref(); + epsilonForm = new Forest.Many(); epsilonForm.merge(firstp().rewrite(null, false)); return epsilonForm; } - protected abstract Forest postReduce(Input.Location loc, Forest[] args, Position p); + protected abstract Forest postReduce(Input.Region loc, Forest[] args, Position p); // Position ////////////////////////////////////////////////////////////////////////////// /** the imaginary position before or after an element of a sequence; corresponds to an "LR item" */ - public class Position implements IntegerMappable { + class Position implements IntegerMappable { private Forest zero = null; public Forest zero() { @@ -124,8 +133,8 @@ public abstract class Sequence extends Element implements Iterable { // Position ///////////////////////////////////////////////////////////////////////////////// - final Forest rewrite(Input.Location loc) { return rewrite(loc, true); } - private final Forest rewrite(Input.Location loc, boolean epsilonCheck) { + final Forest rewrite(Input.Region loc) { return rewrite(loc, true); } + private final Forest rewrite(Input.Region loc, boolean epsilonCheck) { if (epsilonCheck && this==firstp()) return epsilonForm(); for(int i=0; i { if (holder[i]==null) throw new Error("bad " + i); } Forest ret = Sequence.this.postReduce(loc, holder, this); - for(int k=0; k { sb.append("-> "); sb.append(follow); } + for(Sequence s : needs) { + sb.append("& "); + sb.append(s); + } + for(Sequence s : hates) { + sb.append("&~ "); + sb.append(s); + } return sb; } @@ -177,69 +194,78 @@ public abstract class Sequence extends Element implements Iterable { private final Object result; public Constant(Element[] e, Object result) { super(e); this.result = result; } Sequence _clone() { return new Constant(elements, result); } - public Forest postReduce(Input.Location loc, Forest[] args, Position p) { - return (Forest)Forest.leaf(loc, result, p); + public Forest postReduce(Input.Region loc, Forest[] args, Position p) { + return (Forest)Forest.create(loc, result, null, false); } static class Drop extends Constant { - Sequence _clone() { return new Drop(elements, lame); } - public Drop(Element[] e, boolean lame) { - super(e, null); - this.lame = lame; - } + Sequence _clone() { return new Drop(elements); } + public Drop(Element[] e) { super(e, null); } } static class Empty extends Sequence.Constant.Drop { Sequence _clone() { return new Empty(); } - public Empty() { super(new Element[] { }, false); } } + public Empty() { super(new Element[] { }); } } } static class Singleton extends Sequence { private final int idx; public Singleton(Element e) { this(new Element[] { e }, 0); } public Singleton(Element[] e, int idx) { super(e); this.idx = idx; } - public Forest postReduce(Input.Location loc, Forest[] args, Position p) { return (Forest)Forest.singleton(loc, args[idx], p); } + public Forest postReduce(Input.Region loc, Forest[] args, Position p) { return args[idx]; } Sequence _clone() { return new Singleton(elements,idx); } } - public static Unwrap unwrap(Element[] e, Object tag, boolean[] drops) { return new Unwrap(e, tag, drops); } static class Unwrap extends Sequence { private boolean[] drops; private final Object tag; public Unwrap(Element[] e, Object tag) { super(e); this.drops = null; this.tag = tag; } public Unwrap(Element[] e, Object tag, boolean[] drops) { super(e); this.drops = drops; this.tag = tag; } - Sequence _clone() { return new Unwrap(elements, drops); } - public Forest postReduce(Input.Location loc, Forest[] args, Position p) { + Sequence _clone() { return new Unwrap(elements, tag, drops); } + public Forest postReduce(Input.Region loc, Forest[] args, Position p) { for(int i=0; i[] args2 = new Forest[count]; int j = 0; for(int i=0; i tagf; + public RegionRewritingSequence(Functor tagfunctor, Element[] e, boolean[] drops) { + super(null, e, drops); + this.tagf = tagfunctor; + } + public Forest postReduce(Input.Region loc, Forest[] args, Position p) { + this.tag = tagf.invoke(loc); + Forest ret = super.postReduce(loc, args, p); + this.tag = null; + return ret; } } static class RewritingSequence extends Sequence { - /*private*/public final Object tag; + /*private*/public /*final*/ Object tag; private final boolean[] drops; - private final Object[] labs; private int count = 0; - Sequence _clone() { return new RewritingSequence(tag, elements, labs, drops); } - public RewritingSequence(Object tag, Element[] e, Object[] labs) { this(tag, e, labs, null); } - public RewritingSequence(Object tag, Element[] e, Object[] labs, boolean[] drops) { + Sequence _clone() { return new RewritingSequence(tag, elements, drops); } + public RewritingSequence(Object tag, Element[] e) { this(tag, e, null); } + public RewritingSequence(Object tag, Element[] e, boolean[] drops) { super(e); this.tag = tag; this.drops = drops == null ? new boolean[e.length] : drops; for(int i=0; i Forest postReduce(Input.Location loc, Forest[] args, Position p) { + public Forest postReduce(Input.Region loc, Forest[] args, Position p) { Forest[] args2 = new Forest[count]; - Object[] labs2 = new Object[count]; int j = 0; - for(int i=0; i { } } - // Repeat ////////////////////////////////////////////////////////////////////////////// - - /** repeat zero or one times */ - public static Element maybe(Element e) { return new Repeat(e, true, false, null, null); } - public static Element maybe(Element e, Object tag) { return new Repeat(e, true, false, null, tag); } - /** repeat zero or more times */ - public static Element many0(Element e) { return new Repeat(e, true, true, null, null); } - public static Element many0(Element e, Object tag) { return new Repeat(e, true, true, null, tag); } - /** repeat zero or more times, separated by sep */ - public static Element many0(Element e, Element sep) { return new Repeat(e, true, true, sep, null); } - public static Element many0(Element e, Element sep, Object tag) { return new Repeat(e, true, true, sep, tag); } - /** repeat one or more times */ - public static Element many1(Element e) { return new Repeat(e, false, true, null, null); } - public static Element many1(Element e, Object tag) { return new Repeat(e, false, true, null, tag); } - /** repeat one or more times, separated by sep */ - public static Element many1(Element e, Element sep) { return new Repeat(e, false, true, sep, null); } - public static Element many1(Element e, Element sep, Object tag) { return new Repeat(e, false, true, sep, tag); } - - /** repeat zero or more times, matching a maximal sequence of atoms */ - public static Element maximal0(Atom e) { return new Repeat.Maximal(e, true, true, null); } - public static Element maximal0(Atom e, Object tag) { return new Repeat.Maximal(e, true, true, tag); } - /** repeat one or more times, matching a maximal sequence of atoms */ - public static Element maximal1(Atom e) { return new Repeat.Maximal(e, false, true, null); } - public static Element maximal1(Atom e, Object tag) { return new Repeat.Maximal(e, false, true, tag); } - /** repeat one or more times, separated by an atom sep, matching a maximal sequence */ - public static Element maximal1(Element e, Atom sep) { return new Repeat.Maximal(e, false, true, sep, null); } - public static Element maximal1(Element e, Atom sep, Object tag) { return new Repeat.Maximal(e, false, true, sep, tag); } - - public static Element repeatMaximal(Atom e, boolean zero, boolean many, Object tag) { - return new Repeat.Maximal(e, zero, many, tag); } - public static Element repeatMaximal(Element e, boolean zero, boolean many, Atom sep, Object tag) { - return new Repeat.Maximal(e, zero, many, sep, tag); } - public static Element repeat(Element e, boolean zero, boolean many, Object tag) { - return new Repeat(e, zero, many, tag); } - public static Element repeat(Element e, boolean zero, boolean many, Element sep, Object tag) { - return new Repeat(e, zero, many, sep, tag); } }