}
/** adds an alternative */
- public void add(Sequence s) {
- /*
- FIXME
+ public Union add(Sequence s) {
if (viewed)
- throw new RuntimeException("attempt to add a Sequence to a Union that has already been examined:\n "+this);
- */
- if (alternatives.contains(s)) return;
+ throw new RuntimeException("once Union.contains() or Union.iterator() has been invoked, "+
+ "you may not add any more Sequences to it\n "+
+ " union in question: " + this);
+ if (s.needed_or_hated)
+ throw new RuntimeException("you may not add a conjunct directly to a Union");
+ s.in_a_union = true;
+ if (alternatives.contains(s)) return this;
alternatives.add(s);
+ return this;
}
/** adds a one-element sequence */
// Epsilon Form //////////////////////////////////////////////////////////////////////////////
- // FIXME
- //private Forest.Many epsilonForm = null;
+ private Forest.Many epsilonForm = null;
Forest epsilonForm(Input.Region loc) {
- //if (epsilonForm != null) return epsilonForm;
+ // FIXME: this is pretty ugly...
+ viewed = true;
+ if (epsilonForm != null) return epsilonForm;
Forest.Many epsilonForm = new Forest.Many();
- for(Sequence s : this) {
- // FIXME FIXME FIXME
- if (new Walk.Cache().possiblyEpsilon(s))
+ Cache cache = new Cache(null, null);
+ for(Sequence s : this)
+ if (cache.possiblyEpsilon(s))
epsilonForm.merge(s.epsilonForm(loc));
- }
return epsilonForm;
}
String getName() { return name==null ? "(anon_union)" : name; }
public String toString() {
- viewed = true;
+ // technically this should be turned on, but we don't make a big deal
+ //viewed = true;
if (name != null) return name;
StringBuffer sb = new StringBuffer();
sb.append("(");
/** display this union in long/expanded form */
public StringBuffer toString(StringBuffer sb) {
- viewed = true;
+ // technically this should be turned on, but we don't make a big deal
+ //viewed = true;
if (synthetic) return sb;
boolean first = true;
String before = StringUtil.pad(15, getName()) + " = ";