\[\eqn{Foreign Inclusion}{
\bigforall_{D \in \foreign} D \isin C \equiv D \leq C
}\]
-\[\eqn{Foreign Contents}{
+\[\eqn{Foreign Ancestry}{
\bigforall_{C \in \foreign}
D \le C \implies \isforeign{D}
}\]
+\[\eqn{Bases' Children}{
+ C \hasparent D \land D \in \pdn
+ \implies
+ C \in \pdn \lor C \in \pdy
+}\]
We also assign each new commit $C$ to zero or one of the sets $\p$, as
stated in the definition of $\patchof{C}$ in the summary for each kind