From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Fri, 16 Mar 2012 22:53:39 +0000 (+0000)
Subject: extend Self Tip Inpatch
X-Git-Tag: f0.2~7
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=topbloke-formulae.git;a=commitdiff_plain;h=57f83cd8bc6bcf23e45739c00c83c9a8672ae701

extend Self Tip Inpatch
---

diff --git a/lemmas.tex b/lemmas.tex
index 577f513..aeb6564 100644
--- a/lemmas.tex
+++ b/lemmas.tex
@@ -56,14 +56,16 @@ So by Base Acyclic $D \isin B \implies D \notin \py$.
 \subsection{Tip Self Inpatch}
 Given Exclusive Tip Contents and Base Acyclic for $C$,
 $$
-  \bigforall_{C \in \py} C \haspatch \p
+  \bigforall_{C \in \py} C \haspatch \p \land \neg[ C \nothaspatch \p ]
 $$
 Ie, tip commits contain their own patch.
 
 \proof{
 Apply Exclusive Tip Contents to some $D \in \py$:
 $ \bigforall_{C \in \py}\bigforall_{D \in \py}
-  D \isin C \equiv D \le C $
+  D \isin C \equiv D \le C $.
+Thus $C \haspatch \p$.  
+And, since $C \le C$, $C \isin C$.  Therefore $\neg[ C \nothaspatch \p ]$
 }
 
 \subsection{Exact Ancestors}