X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2FRepeat.java;h=c85bfc6497dd140ab22b891e0e00a37e47a8c151;hb=3c03a0a1131b46a23ccfdeab2cb4fbd59ee05b7a;hp=2365cbd2e579c69b7bdb236fa29a3f81b4d8cd6e;hpb=0a0227b9180534d2a431f3d6e08a398bde2244c4;p=sbp.git
diff --git a/src/edu/berkeley/sbp/Repeat.java b/src/edu/berkeley/sbp/Repeat.java
index 2365cbd..c85bfc6 100644
--- a/src/edu/berkeley/sbp/Repeat.java
+++ b/src/edu/berkeley/sbp/Repeat.java
@@ -8,56 +8,54 @@ import java.lang.reflect.*;
import java.lang.ref.*;
/** currently this class exports only static methods to create repetitions; there are no public instance methods or constructors */
-public class Repeat extends Union {
+class Repeat extends Union {
- /** repeat zero or one times */
- public static Repeat maybe(Element e) { return new Repeat(e, true, false); }
- /** repeat zero or more times */
- public static Repeat many0(Element e) { return new Repeat(e, true, true); }
- /** repeat zero or more times, separated by sep */
- public static Repeat many0(Element e, Element sep) { return new Repeat(e, true, true, sep); }
- /** repeat one or more times */
- public static Repeat many1(Element e) { return new Repeat(e, false, true); }
- /** repeat one or more times, separated by sep */
- public static Repeat many1(Element e, Element sep) { return new Repeat(e, false, true, sep); }
- public static Maximal maximal(Element e) { return new Maximal(e); }
-
- // Instance //////////////////////////////////////////////////////////////////////////////
-
- final boolean zeroOkay, manyOkay;
- final Element e;
- final Element separator;
-
- Repeat(final Element e, boolean zeroOkay, boolean manyOkay) { this(e, zeroOkay, manyOkay, null); }
- Repeat(final Element e, boolean zeroOkay, boolean manyOkay, Element separator) {
- super(e+(!manyOkay ? "?" : (zeroOkay ? "*" : "+")), true);
- this.e = e;
- this.zeroOkay = zeroOkay;
- this.manyOkay = manyOkay;
- this.separator = separator;
- if (zeroOkay) {
+ public Repeat(final Element e, boolean zeroOkay, boolean manyOkay, Object tag) {
+ this(e, zeroOkay, manyOkay, null, false, tag); }
+ public Repeat(final Element e, boolean zeroOkay, boolean manyOkay, final Element separator, Object tag) {
+ this(e, zeroOkay, manyOkay, separator, false, tag); }
+ protected Repeat(final Element e, boolean zeroOkay, boolean manyOkay, final Element separator, boolean maximal, Object tag) {
+ super(e+(!manyOkay ? "?" : (zeroOkay ? (maximal ? "**" : "*") : (maximal ? "++" : "+")))+(separator==null?"":("/"+separator)), true);
+ if (zeroOkay && !manyOkay) {
add(new Sequence.Constant.Empty());
- if (manyOkay) add(new Sequence.Singleton(many1(e, separator), null, null));
- else add(new Sequence.Singleton(e, null, null));
+ add(new Sequence.Singleton(e));
+ return;
+ }
+ if (zeroOkay) {
+ add(new Sequence.RewritingSequence(tag, new Element[] { }, null));
+ //add(new Sequence.Constant.Empty());
+ // FUGLY
+ add(new Sequence.Singleton(Sequence.many1(e, separator, tag)));
} else {
- add(new Sequence.RewritingSequence(null, new Element[] { e }, null, null));
- if (this.separator==null) {
- add(new Sequence.Unwrap(new Element[] { e, Repeat.this }, null, null));
- } else {
- add(new Sequence.Unwrap(new Element[] { e, this.separator, Repeat.this }, new boolean[] { false, true, false }, null, null));
- }
+ add(new Sequence.RewritingSequence(tag, new Element[] { e }, null));
+ if (separator==null)
+ add(new Sequence.Unwrap(new Element[] { e, Repeat.this }, tag));
+ else
+ add(new Sequence.Unwrap(new Element[] { e, separator, Repeat.this }, tag, new boolean[] { false, true, false }));
}
}
- static class MaximalSequence extends Sequence.Singleton {
- private final Element e;
- public String toString() { return e+"@";}
- public MaximalSequence(Element e) { super(e, null, null); this.e = e; }
- }
- static class Maximal extends Union {
- public Maximal(final Element e) {
- super(e+"+", true);
- add(new MaximalSequence(e));
+ public static class Maximal extends Repeat {
+ public Maximal(final Element e, boolean zeroOkay, boolean manyOkay, final Atom separator, Object tag) {
+ super(e, zeroOkay, manyOkay, separator, true, tag);
+ if (zeroOkay && separator != null)
+ throw new RuntimeException("cannot create a maximal repetition of zero or more items with a separator (yet): " + this);
+ for(Sequence s : this)
+ s.follow = new Invert(separator);
+ }
+ public Maximal(final Atom e, boolean zeroOkay, boolean manyOkay, Object tag) {
+ super(e, zeroOkay, manyOkay, null, true, tag);
+ for(Sequence s : this)
+ s.follow = new Invert(e);
}
}
+
+
+ /** an atom which tracks the inverse of some other atom */
+ private static class Invert extends Atom {
+ private final Atom a;
+ public Invert(Atom a) { this.a = a; }
+ public Topology top() { return a.complement(); }
+ public String toString() { return "~"+a; }
+ }
}