package edu.berkeley.sbp;
import edu.berkeley.sbp.util.*;
import edu.berkeley.sbp.*;
import edu.berkeley.sbp.*;
import java.io.*;
import java.util.*;
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 {
/** 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) {
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) {
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));
}
}
}