refactored Repeat

[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 2365cbd..9b6d6bb 100644 (file)
--- a/src/edu/berkeley/sbp/Repeat.java
+++ b/src/edu/berkeley/sbp/Repeat.java
@@ -20,44 +20,31 @@ public class Repeat extends Union {
     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); }
-    public  static Maximal maximal(Element e)           { return new Maximal(e); }
 
-    // Instance //////////////////////////////////////////////////////////////////////////////
-    
-    final boolean zeroOkay, manyOkay;
-    final Element e;
-    final Element separator;
+    /** 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); }
 
-    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;
+    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) {
+        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) {
             add(new Sequence.Constant.Empty());
             if (manyOkay) add(new Sequence.Singleton(many1(e, separator), null, null));
             else          add(new Sequence.Singleton(e, null, null));
         } else {
             add(new Sequence.RewritingSequence(null, new Element[] { e }, null, null));
-            if (this.separator==null) {
+            if (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));
-            }
-        }
-    }
-
-    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));
+            else
+                add(new Sequence.Unwrap(new Element[] { e, separator,      Repeat.this }, new boolean[] { false, true, false }, null, null));
         }
+        if (maximal) for(Sequence s : this) s.noFollow = separator==null ? e : separator;
     }
 }