pseudomerge: commentary about foreign apparently-pseudo merges

[topbloke-formulae.git] / strategy.tex

diff --git a/strategy.tex b/strategy.tex
index 1e8ee0156f5846bec3d54e4852396c703c432564..a4716b313dd577c5e74c6e1a7afe4f39ba8be082 100644 (file)
--- a/strategy.tex
+++ b/strategy.tex
@@ -74,7 +74,7 @@ All the input commits to the update algorithm.  (See below.)
 The topmost patch which we are trying to update.  This and
 all of its dependencies will be updated.
 
-\item[ $h : \pc^{+/-} \mapsto \set H_{\pc^{+/-}}$ ]
+\item[ $h : \pc^{+/-} \mapsto \set H^{\pc^{+/-}}$ ]
 Function for getting the existing heads $\set H$ of the branch $\pc^{+/-}$.
 These are the heads which will be merged and used in this update.
 This will include the current local and remote git refs, as desired.
@@ -104,8 +104,23 @@ during the update algorithm).
 
 \item[ $\tipcn, \tipcy$ ]
 The new tips of the git branches $\pcn$ and $\pcy$, containing
-all the correct commits (and the correct other patches), as
-generated by the Traversal phase of the update algorithm.
+all the appropriate commits (and the appropriate other patches),
+as generated by the Traversal phase of the update algorithm.
 
-\end{basedescript}
+\item[ $\allreach$ ]
+The set of all reachable commits.
+
+A reachable commit is one we might refer to explicitly in any of these
+algorithms, and any ancestor of such a commit.  We explicitly
+enumerate all of the input commits ($\allsrcs$), so the reachable
+commits are originally the input commits and their ancestors.
+
+$\allreach$ varies over time as we generate more commits.  Each
+commit we generate will have only reachable commits as ancestors, so
+generating a new commit (only) adds that new commit to $\allreach$.
 
+\item[ $\allreachof{\py}$ ]
+The set of reachable commits at the point where we have just generated
+$\tippy$, i.e. just after $\alg{Merge-Tip}(\p)$.
+
+\end{basedescript}