@Override public Set<Statement> apply(final IGASState<Set<Statement>,Set<Statement>,Set<Statement>> state,final Value u,final Set<Statement> sum){
  if (sum != null) {
    final Set<Statement> us=state.getState(u);
    us.addAll(sum);
    return us;
  }
  return null;
}

@ Override public Set < Statement > apply ( final IGASState < Set < Statement > , Set < Statement > , Set < Statement > > state , final Value u , final Set < Statement > sum ) { if ( sum != null ) { final Set < Statement > us = state . getState ( u ) ; us . addAll ( sum ) ; return us ; } return null ; }
union the gathered edges with those already decorating the vertex .
