X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=topbloke-formulae.git;a=blobdiff_plain;f=invariants.tex;h=ac0558a82bd9fd202ba0e308d543801eba8a1b4c;hp=736fb8ee569ed5a2791bfae5b1c817cd95cfaa23;hb=1768ad396360b5f7145450858b4bae1e9d1c7b05;hpb=fd4fcf610bbe38767f7aba836c233bdc46e513e3

diff --git a/invariants.tex b/invariants.tex
index 736fb8e..ac0558a 100644
--- a/invariants.tex
+++ b/invariants.tex
@@ -22,11 +22,16 @@ We maintain these each time we construct a new commit. \\
   \bigforall_{C,\p} C \haspatch \p \implies \pendsof{C}{\py} = \{ T \}
 }\]
 \[\eqn{Foreign Inclusion}{
-  \bigforall_{D \text{ s.t. } \patchof{D} = \foreign} D \isin C \equiv D \leq C
+  \bigforall_{D \in \foreign} D \isin C \equiv D \leq C
 }\]
-\[\eqn{Foreign Contents}{
-  \bigforall_{C \text{ s.t. } \patchof{C} = \foreign}
-    D \le C \implies \patchof{D} = \foreign
+\[\eqn{Foreign Ancestry}{
+  \bigforall_{C \in \foreign}
+    D \le C \implies \isforeign{D}
+}\]
+\[\eqn{Bases' Children}{
+  C \hasparent D \land D \in \pdn
+    \implies
+  C \in \pdn \lor C \in \pdy
 }\]
 
 We also assign each new commit $C$ to zero or one of the sets $\p$, as