// then is b the list of alle terminal symbols from FIRST(va)
do
{
if (productiondefinition.getSymbol(pos).isTerminal())
{
b2.clear();
b2.addSymbol(productiondefinition.getSymbol(pos));
}
else
b2 = _firstsets.getFirstSet(productiondefinition.getSymbol(pos));
b.addSymbolList(b2);