checkpoint

[sbp.git] / src / edu / berkeley / sbp / Repeat.java

diff --git a/src/edu/berkeley/sbp/Repeat.java b/src/edu/berkeley/sbp/Repeat.java
index aa91a64..037e67d 100644 (file)
--- a/src/edu/berkeley/sbp/Repeat.java
+++ b/src/edu/berkeley/sbp/Repeat.java
@@ -8,43 +8,46 @@ 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 <tt>sep</tt> */
-    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 <tt>sep</tt> */
-    public  static Repeat many1(Element e, Element sep) { return new Repeat(e, false, true, sep); }
-
-    /** repeat zero or more times, matching a maximal sequence of atoms */
-    public  static Repeat maximal0(Element e)              { return new Repeat(e, true, true, null, true); }
-    /** repeat one or more times, matching a maximal sequence of atoms */
-    public  static Repeat maximal1(Element e)              { return new Repeat(e, false, true, null, true); }
-    /** repeat one or more times, separated by an atom <tt>sep</tt>, matching a maximal sequence */
-    public  static Repeat maximal1(Element e, Element sep) { return new Repeat(e, false, true, sep, true); }
-
-    private Repeat(final Element e, boolean zeroOkay, boolean manyOkay) { this(e, zeroOkay, manyOkay, null); }
-    private Repeat(final Element e, boolean zeroOkay, boolean manyOkay, Element separator) { this(e, zeroOkay, manyOkay, separator, false); }
-    private Repeat(final Element e, boolean zeroOkay, boolean manyOkay, final Element separator, boolean maximal) {
+    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 (maximal && zeroOkay && separator != null)
-            throw new RuntimeException("cannot create a maximal repetition of zero or more items with a separator (yet): " + this);
-        if (zeroOkay) {
+        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));
+            add(new Sequence.RewritingSequence(tag, new Element[] { e }, null));
             if (separator==null)
-                add(new Sequence.Unwrap(new Element[] { e,                 Repeat.this }));
+                add(new Sequence.Unwrap(new Element[] { e,                 Repeat.this }, tag));
             else
-                add(new Sequence.Unwrap(new Element[] { e, separator,      Repeat.this }, new boolean[] { false, true, false }));
+                add(new Sequence.Unwrap(new Element[] { e, separator,      Repeat.this }, tag, new boolean[] { false, true, false }));
         }
-        if (maximal) for(Sequence s : this) s.noFollow = separator==null ? e : separator;
     }
+
+    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 = (Atom)separator.complement();
+        }
+        public Maximal(final Atom e, boolean zeroOkay, boolean manyOkay, Object tag) {
+            super(e, zeroOkay, manyOkay, null, true, tag);
+            for(Sequence s : this)
+                s.follow = (Atom)e.complement();
+        }
+    }
+
 }