pub fn case<N, C, D, B, Row1, Row2, SessionSum, InjectSessionSum>(
_: N,
cont1: impl FnOnce(InjectSessionSum) -> SessionSum + Send + 'static
) -> PartialSession<C, B> where
B: Protocol,
C: Context,
D: Context,
Row1: Send + 'static,
Row1: ToRow<Row = Row2>,
Row2: RowCon,
Row2: ElimSum,
Row2: SplitRow,
Row2: SumFunctor,
Row2: IntersectSum,
Row2: SumFunctorInject,
Row2: SumApp<InternalSessionF<N, C, B, Row1, D>, Applied = SessionSum>,
Row2: FlattenSumApp<InjectSessionF<N, C, B, Row1, D>, FlattenApplied = InjectSessionSum>,
N: ContextLens<C, InternalChoice<Row1>, Empty, Deleted = D>,
SessionSum: Send + 'static,
InjectSessionSum: Send + 'static,