X-Git-Url: http://git.megacz.com/?p=sbp.git;a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2FSequence.java;h=430f29813c37952956b6cf0762f4a4c03219840f;hp=8995b5c8576c96651d6d975037ec7822ebb3c28f;hb=260e46cff8995fb5a01e94c1a707d0ffff0a5382;hpb=72a191a1440fcdc484700238e8be1384ccc56e06 diff --git a/src/edu/berkeley/sbp/Sequence.java b/src/edu/berkeley/sbp/Sequence.java index 8995b5c..430f298 100644 --- a/src/edu/berkeley/sbp/Sequence.java +++ b/src/edu/berkeley/sbp/Sequence.java @@ -1,3 +1,5 @@ +// Copyright 2006-2007 all rights reserved; see LICENSE file for BSD-style license + package edu.berkeley.sbp; import edu.berkeley.sbp.util.*; import edu.berkeley.sbp.*; @@ -7,141 +9,231 @@ 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 { - // Static Constructors ////////////////////////////////////////////////////////////////////////////// + protected final Element[] elements; + + boolean needed_or_hated = false; + boolean in_a_union = false; + + final HashSet needs = new HashSet(); + final HashSet hates = new HashSet(); + + // FIXME: these are ugly -- migrate into Grammar + HashMap canNeed = new HashMap(); + HashMap canKill = new HashMap(); + + final Position firstp; + + Atom follow = null; - public abstract Sequence and(Sequence s); - public abstract Sequence not(Sequence s); + private static int global_sernum = 0; + private int sernum = global_sernum++; + int[] needs_int() { + int[] ret = new int[needs.size()]; + int i = 0; + for(Sequence s : needs) ret[i++] = s.sernum; + return ret; + } + int[] hates_int() { + int[] ret = new int[hates.size()]; + int i = 0; + for(Sequence s : hates) ret[i++] = s.sernum; + return ret; + } - private void needs(Sequence s) { s.needed.add(this); needs.add(s); } - private void hates(Sequence s) { s.hated.add(this); hates.add(s); } - /** the empty sequence (matches the empty string) */ - public static final Sequence empty = new Sequence.Constant.Empty(); + // Static Constructors ////////////////////////////////////////////////////////////////////////////// + + /** create a sequence of one element */ + public static Sequence create(Element e) { return create(new Element[] { e }, 0); } - /** 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, null, null, lame); } + /** 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, insert a constant into the output tree */ - public static Sequence constant(Element[] e, Object o) { return new Constant(e, o, null, null); } + /** create a sequence which always evaluates to a constant result */ + public static Sequence create(Object result, Element[] e) { + return new RewritingSequence(result, e, trues(e.length)); } - /** 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, null, null); } + private static boolean[] trues(int length) { + boolean[] ret = new boolean[length]; + for(int i=0; ie 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 lifts which (if any) child trees to lift **/ - public static Sequence rewritingSequence(Object tag, Element[] e, boolean[] drops) { return new RewritingSequence(tag, e, drops, null, null); } - - //////////////////////////////////////////////////////////////////////////////// + public static Sequence create(Object head, Element[] e, boolean[] drop) { + return create(head, e, drop, new boolean[e.length]); } + public static Sequence create(Object head, Element[] e, boolean[] drop, boolean[] lifts) { + if (lifts==null) lifts = new boolean[e.length]; + return new RewritingSequence(head, e, drop, lifts); + } - public Element noFollow = null; - public String name = null; - public void setName(String name) { this.name = name; } - public final Topology noFollow() { return noFollow==null ? null : noFollow.toAtom(); } + /** return a new sequence identical to this one, but with a positive conjunct s */ + public Sequence and(Sequence s) { + if (s.in_a_union) + throw new RuntimeException("you may not use a sequence as a conjunct if it belongs to a Union"); + Sequence ret = dup(); + ret.needs.add(s); + s.needed_or_hated=true; + return ret; + } - Topology toAtom() { - if (elements.length!=1) throw new RuntimeException("cannot invoke toAtom() on a Sequence with " + elements.length + " elements: " + this); - return elements[0].toAtom(); + /** return a new sequence identical to this one, but with a negative conjunct s */ + public Sequence andnot(Sequence s) { + if (s.in_a_union) + throw new RuntimeException("you may not use a sequence as a conjunct if it belongs to a Union"); + Sequence ret = dup(); + ret.hates.add(s); + s.needed_or_hated=true; + 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; + abstract Sequence _clone(); + private Sequence dup() { + Sequence ret = _clone(); + for(Sequence s : needs) { ret.needs.add(s); } + for(Sequence s : hates) { ret.hates.add(s); } + ret.follow = follow; + return ret; + } + + Iterable needs() { return needs; } + Iterable hates() { return hates; } - final Position firstp; - Position firstp() { return firstp; } + Pos firstp() { return firstp; } + Pos lastp() { return firstp().last(); } public Iterator iterator() { return new ArrayIterator(elements); } - protected Sequence(Element[] elements, HashSet and, HashSet not) { - if (and!=null) for(Sequence s : and) { needs.add(s); s.needed.add(this); } - if (not!=null) for(Sequence s : not) { hates.add(s); s.hated.add(this); } + protected Sequence(Element[] elements) { this.elements = elements; - this.firstp = new Position(0); + for(int i=0; i Forest postReduce(Input.Location loc, Forest[] args); + 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 { + static abstract class Pos implements IntegerMappable, Comparable, Serializable { + + public int ord = -1; + private transient Sequence owner; + + public int ord() { return ord; } + + final Forest[] holder; + + Pos(int len, Sequence owner) { + this.owner = owner; + this.holder = new Forest[len]; + } + + public abstract int provides(); + public abstract int[] needs(); + public abstract int[] hates(); + public abstract boolean owner_needed_or_hated(); - private Forest zero = null; - public Forest zero() { - if (zero != null) return zero; - if (pos > 0) throw new Error(); - return zero = rewrite(null); + public abstract boolean isFirst(); + public abstract boolean isLast(); + public abstract Pos last(); + public abstract Pos prev(); + public abstract Pos next(); + + /** the element which produces the sequence to which this Position belongs */ + public Sequence owner() { return owner; } + + abstract Element element(); + + public abstract int numPops(); + public abstract Forest rewrite(Input.Region loc); + } + + /** the imaginary position before or after an element of a sequence; corresponds to an "LR item" */ + private static class Position extends Pos implements IntegerMappable { + /* + public Pos getPos() { + return new DumbPos(elements.length, provides(), needs(), hates(), owner_needed_or_hated(), numPops(), + public int provides(); + public int[] needs(); + public int[] hates(); + public boolean owner_needed_or_hated(); + public int numPops(); + public Forest rewrite(Input.Region loc) + }; } + */ + public int numPops() { return pos; } + final int pos; + private final Position next; + private final Position prev; - final int pos; - private final Position next; - final Forest[] holder; + public int provides() { return owner().sernum; } + public int[] needs() { return owner().needs_int(); } + public int[] hates() { return owner().hates_int(); } + public boolean owner_needed_or_hated() { return owner().needed_or_hated; } - private Position(int pos) { + private Position(Sequence owner, int pos, Position prev) { + super(owner.elements.length,owner); this.pos = pos; - this.next = pos==elements.length ? null : new Position(pos+1); - this.holder = new Forest[elements.length]; + this.next = pos==owner.elements.length ? null : new Position(owner, pos+1, this); + this.prev = prev; + } + + public int compareTo(Pos p) { + return ord - ((Position)p).ord; } - boolean isFirst() { return pos==0; } + public boolean isFirst() { return pos==0; } + public int pos() { return pos; } /** the element immediately after this Position, or null if this is the last Position */ - public Element element() { return pos>=elements.length ? null : elements[pos]; } - - /** the element which produces the sequence to which this Position belongs */ - public Sequence owner() { return Sequence.this; } + public Element element() { return pos>=owner().elements.length ? null : owner().elements[pos]; } /** the next Position (the Position after this.element()) */ public Position next() { return next; } /** true iff this Position is the last one in the sequence */ public boolean isLast() { return next()==null; } + public Position last() { return isLast() ? this : next().last(); } + public Position prev() { return prev; } // Position ///////////////////////////////////////////////////////////////////////////////// - final Forest rewrite(Input.Location loc) { - if (this==firstp()) return epsilonForm(); - return rewrite2(loc); - } - - final Forest rewrite2(Input.Location loc) { + public final Forest rewrite(Input.Region loc) { + if (isFirst()) return owner().epsilonForm(loc); for(int i=0; i ret = Sequence.this.postReduce(loc, holder); - for(int k=0; k { } private static int master_position_idx = 0; + // toString ////////////////////////////////////////////////////////////////////////////// public String toString() { return toString(new StringBuffer(), false).toString(); } StringBuffer toString(StringBuffer sb) { return toString(sb, true); } StringBuffer toString(StringBuffer sb, boolean spacing) { for(int i=0; i "); + sb.append(follow); + } + for(Sequence s : needs) { + sb.append("& "); + sb.append(s); + } + for(Sequence s : hates) { + sb.append("&~ "); + sb.append(s); + } return sb; } - // Specialized Subclasses ////////////////////////////////////////////////////////////////////////////// - static class Constant extends Sequence { - private final Object result; - public Constant(Element[] e, Object result, HashSet and, HashSet not) { super(e, and, not); this.result = result; } - public Sequence and(Sequence s) { Sequence ret = new Constant(elements, result, needs, hates); ret.needs(s); return ret; } - public Sequence not(Sequence s) { Sequence ret = new Constant(elements, result, needs, hates); ret.hates(s); return ret; } - public Forest postReduce(Input.Location loc, Forest[] args) { - return (Forest)Forest.leaf(loc, result); - } - static class Drop extends Constant { - public Drop(Element[] e, HashSet and, HashSet not, boolean lame) { - super(e, null, and, not); - this.lame = lame; - } - } - static class Empty extends Sequence.Constant.Drop { public Empty() { super(new Element[] { }, null, null, false); } } - } - static class Singleton extends Sequence { private final int idx; - public Singleton(Element e, HashSet and, HashSet not) { this(new Element[] { e }, 0, and, not); } - public Singleton(Element[] e, int idx, HashSet and, HashSet not) { super(e, and, not); this.idx = idx; } - public Forest postReduce(Input.Location loc, Forest[] args) { return (Forest)Forest.singleton(loc, args[idx]); } - public Sequence and(Sequence s) { Sequence ret = new Singleton(elements, idx, needs, hates); ret.needs(s); return ret; } - public Sequence not(Sequence s) { Sequence ret = new Singleton(elements, idx, needs, hates); ret.hates(s); return ret; } - } - - public static class Unwrap extends Sequence { - private boolean[] drops; - public Unwrap(Element[] e, HashSet and, HashSet not) { super(e, and, not); this.drops = null; } - public Unwrap(Element[] e, boolean[] drops, HashSet and, HashSet not) { super(e, and, not); this.drops = drops; } - public Sequence and(Sequence s) { Sequence ret = new Unwrap(elements, drops, needs, hates); ret.needs(s); return ret; } - public Sequence not(Sequence s) { Sequence ret = new Unwrap(elements, drops, needs, hates); ret.hates(s); return ret; } - public Forest postReduce(Input.Location loc, Forest[] args) { - for(int i=0; i[] args2 = new Forest[count]; - int j = 0; - for(int i=0; i Forest postReduce(Input.Region loc, Forest[] args, Position p) { return args[idx]; } + Sequence _clone() { return new Singleton(elements,idx); } + Forest epsilonForm(Input.Region loc) { + return ((Union)elements[idx]).epsilonForm(loc); } } static class RewritingSequence extends Sequence { - /*private*/public final Object tag; + private final Object tag; private final boolean[] drops; - private int count = 0; - public Sequence and(Sequence s) { Sequence ret = new RewritingSequence(tag, elements, drops, needs, hates); ret.needs(s); return ret; } - public Sequence not(Sequence s) { Sequence ret = new RewritingSequence(tag, elements, drops, needs, hates); ret.hates(s); return ret; } - public RewritingSequence(Object tag, Element[] e, HashSet and, HashSet not) { this(tag, e, null, and, not); } - public RewritingSequence(Object tag, Element[] e, boolean[] drops, HashSet and, HashSet not) { - super(e, and, not); + private final boolean[] lifts; + 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) { this(tag, e, drops, new boolean[e.length]); } + public RewritingSequence(Object tag, Element[] e, boolean[] drops, boolean[] lifts) { + super(e); + if (tag==null) throw new Error(); this.tag = tag; this.drops = drops == null ? new boolean[e.length] : drops; + int count = 0; for(int i=0; i Forest postReduce(Input.Location loc, Forest[] args) { - Forest[] args2 = new Forest[count]; + public Forest postReduce(Input.Region loc, Forest[] args, Position p) { + Forest[] args2 = new Forest[lifts.length]; int j = 0; for(int i=0; i "); - sb.append(tag); return sb; } + Forest epsilonForm(Input.Region loc) { + return Forest.create(loc, tag, new Forest[0], lifts); + } } }