int hash = (negativeSuffix.hashCode() ^ negativePrefix.hashCode() ^positivePrefix.hashCode() ^ positiveSuffix.hashCode());  return hash;
return toPattern().hashCode();
  public int hashCode ()  {    int hash = (negativeSuffix.hashCode() ^ negativePrefix.hashCode()		^positivePrefix.hashCode() ^ positiveSuffix.hashCode());		// FIXME.		return hash;	}