X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=topbloke-formulae.git;a=blobdiff_plain;f=article.tex;h=d85a022ff8fb8388f380325f4ffd4ed9e4330d5d;hp=f40f6a2c508b4877d8fe619685ff8f810f20a63a;hb=400772c417bd54383994df5a227df88adc769171;hpb=fc75f297123c083b696f8d5639a4242a12e70f33

diff --git a/article.tex b/article.tex
index f40f6a2..d85a022 100644
--- a/article.tex
+++ b/article.tex
@@ -66,6 +66,9 @@
 \newcommand{\gathbegin}{\begin{gather} \tag*{}}
 \newcommand{\gathnext}{\\ \tag*{}}
 
+\newcommand{\true}{t}
+\newcommand{\false}{f}
+
 \begin{document}
 
 \section{Notation}
@@ -286,7 +289,7 @@ Ancestors of $C$:
 $ D \le C $.
 
 Contents of $C$:
-$ D \isin C \equiv \ldots \lor t \text{ so } D \haspatch C $.
+$ D \isin C \equiv \ldots \lor \true \text{ so } D \haspatch C $.
 
 \subsubsection{For $A \haspatch P, D \neq C$:}
 Ancestors: $ D \le C \equiv D \le A $.
@@ -313,16 +316,33 @@ $\qed$
 If $D = C$, trivial.  For $D \neq C$:
 $D \isin C \equiv D \isin A \equiv D \le A \equiv D \le C$.  $\qed$
 
-\section{Test more symbols}
-
-$ C \haspatch \p $
-
-$ C \nothaspatch \p $
+\section{Merge}
 
-$ \p \patchisin C $
+Merge commits $L$ and $R$ using merge base $M$ ($M < L, M < R$):
+\gathbegin
+ C \hasparents \{ L, R \}
+\gathnext
+ \patchof{C} = \patchof{L}
+\gathnext
+ D \isin C \equiv
+  \begin{cases}
+    (D \isin L \land D \isin R) \lor D = C : & \true \\
+    (D \not\isin L \land D \not\isin R) \land D \neq C : & \false \\
+    \text{otherwise} : & D \not\isin M
+  \end{cases}
+\end{gather}
 
-$ \p \notpatchisin C $
+\subsection{Conditions}
 
-$ \{ B \} \areparents C $
+\[ \eqn{ Merges Exhaustive }{
+ L \in \py => \Bigl[ R \in \py \lor R \in \pn \Bigr]
+}\]
+\[ \eqn{ Tip Merge }{
+ L \in \py \land R \in \py \implies \Bigl[ \text{TBD} \Bigr]
+}\]
+\[ \eqn{ Base Merge }{
+ L \in \py \land R \in \pn \implies \Bigl[ R \ge \baseof{L} \land M =
+   \baseof{L} \Bigr]
+}\]
 
 \end{document}