add ToBag operator (#123) * add ToBag operator Signed-off-by: Stephan Merz <stephan.merz@loria.fr> * improve comment for ToBag operator Signed-off-by: Stephan Merz <stephan.merz@loria.fr> --------- Signed-off-by: Stephan Merz <stephan.merz@loria.fr>
add ToBag operator (#123) * add ToBag operator Signed-off-by: Stephan Merz <stephan.merz@loria.fr> * improve comment for ToBag operator Signed-off-by: Stephan Merz <stephan.merz@loria.fr> --------- Signed-off-by: Stephan Merz <stephan.merz@loria.fr>