@Override
public ImmutableRangeSet<Integer> lookahead(Language lang) {
Frequency ff = lang.lali.consumesInput(first);
switch (ff) {
case NEVER:
return lang.lali.lookahead(second);
case ALWAYS:
return lang.lali.lookahead(first);
case SOMETIMES:
TreeRangeSet<Integer> r = TreeRangeSet.create();
r.addAll(lang.lali.lookahead(first));
r.addAll(lang.lali.lookahead(second));
return ImmutableRangeSet.copyOf(r);
}
throw new AssertionError(ff.name());
}
@Override
public Frequency consumesInput(Language lang) {
Frequency ff = lang.lali.consumesInput(first);
switch (ff) {
case NEVER:
return lang.lali.consumesInput(second);
case ALWAYS:
return ff;
case SOMETIMES:
Frequency sf = lang.lali.consumesInput(second);
switch (sf) {
case ALWAYS:
case SOMETIMES:
return sf;
case NEVER:
return Frequency.SOMETIMES;
}
throw new AssertionError(sf.name());
}
throw new AssertionError(ff.name());
}