1 package edu.berkeley.sbp;
2 import edu.berkeley.sbp.util.*;
3 import edu.berkeley.sbp.*;
4 import edu.berkeley.sbp.*;
7 import java.lang.reflect.*;
8 import java.lang.ref.*;
10 /** currently this class exports only static methods to create repetitions; there are no public instance methods or constructors */
11 public class Repeat extends Union {
13 /** repeat zero or one times */
14 public static Repeat maybe(Element e) { return new Repeat(e, true, false, null, false); }
15 public static Repeat maybe(Element e, Object tag) { return new Repeat(e, true, false, null, false, tag); }
16 /** repeat zero or more times */
17 public static Repeat many0(Element e) { return new Repeat(e, true, true, null, false); }
18 public static Repeat many0(Element e, Object tag) { return new Repeat(e, true, true, null, false, tag); }
19 /** repeat zero or more times, separated by <tt>sep</tt> */
20 public static Repeat many0(Element e, Element sep) { return new Repeat(e, true, true, sep, false); }
21 public static Repeat many0(Element e, Element sep, Object tag) { return new Repeat(e, true, true, sep, false, tag); }
22 /** repeat one or more times */
23 public static Repeat many1(Element e) { return new Repeat(e, false, true, null, false); }
24 public static Repeat many1(Element e, Object tag) { return new Repeat(e, false, true, null, false, tag); }
25 /** repeat one or more times, separated by <tt>sep</tt> */
26 public static Repeat many1(Element e, Element sep) { return new Repeat(e, false, true, sep, false); }
27 public static Repeat many1(Element e, Element sep, Object tag) { return new Repeat(e, false, true, sep, false, tag); }
29 /** repeat zero or more times, matching a maximal sequence of atoms */
30 public static Repeat maximal0(Element e) { return new Repeat(e, true, true, null, true); }
31 public static Repeat maximal0(Element e, Object tag) { return new Repeat(e, true, true, null, true, tag); }
32 /** repeat one or more times, matching a maximal sequence of atoms */
33 public static Repeat maximal1(Element e) { return new Repeat(e, false, true, null, true); }
34 public static Repeat maximal1(Element e, Object tag) { return new Repeat(e, false, true, null, true, tag); }
35 /** repeat one or more times, separated by an atom <tt>sep</tt>, matching a maximal sequence */
36 public static Repeat maximal1(Element e, Element sep) { return new Repeat(e, false, true, sep, true); }
37 public static Repeat maximal1(Element e, Element sep, Object tag) { return new Repeat(e, false, true, sep, true, tag); }
39 private Repeat(final Element e, boolean zeroOkay, boolean manyOkay, final Element separator, boolean maximal) {
40 this(e, zeroOkay, manyOkay, separator, maximal, null); }
41 private Repeat(final Element e, boolean zeroOkay, boolean manyOkay, final Element separator, boolean maximal, Object tag) {
42 super(e+(!manyOkay ? "?" : (zeroOkay ? (maximal ? "**" : "*") : (maximal ? "++" : "+")))+(separator==null?"":("/"+separator)), true);
43 if (maximal && zeroOkay && separator != null)
44 throw new RuntimeException("cannot create a maximal repetition of zero or more items with a separator (yet): " + this);
46 add(new Sequence.Constant.Empty());
47 if (manyOkay) add(new Sequence.Singleton(many1(e, separator)));
48 else add(new Sequence.Singleton(e));
50 add(new Sequence.RewritingSequence(tag, new Element[] { e }, null));
52 add(new Sequence.Unwrap(new Element[] { e, Repeat.this }, tag));
54 add(new Sequence.Unwrap(new Element[] { e, separator, Repeat.this }, tag, new boolean[] { false, true, false }));
56 if (maximal) for(Sequence s : this) s.noFollow = separator==null ? e : separator;