From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Sun, 27 May 2012 17:43:47 +0000 (+0100)
Subject: strategy: new, wip, notational fixes
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=topbloke-formulae.git;a=commitdiff_plain;h=64a3ef281cdbfa63f1c306222d6e3e2b507d21a0

strategy: new, wip, notational fixes
---

diff --git a/strategy.tex b/strategy.tex
index 3412853..9bed7cf 100644
--- a/strategy.tex
+++ b/strategy.tex
@@ -32,12 +32,12 @@ The set of direct dependencies (in the form $\py$)
 requested in the commit $K$ ($K \in \pn$) for the patch $\p$.
 
 \item[ $\pc \hasdirdep \p$ ]
-The Topbloke commit set $\pc$ has as a direct contributor the
-commit set $\p$.  This is an acyclic relation.
+The patch $\pc$ has as a direct dependency the
+patch $\p$.  This is an acyclic relation.
 
 \item[ $\p \hasdep \pq$ ]
-The commit set $\p$ has as direct or indirect contributor the commit
-set $\pq$.
+The patch $\p$ has as direct or indirect dependency the
+patch $\pq$.
 Acyclic; the completion of $\hasdirdep$ into a
 partial order.
 
@@ -50,6 +50,13 @@ the $\le$-maximal elements of $\bigcup_{J \in \set J} \pendsof{J}{\p}$
 Convenience notation for
 $\bigforall_{E \in \pendsof{\set X}{\p}} E \le T$
 
+\item[ $\Gamma_{\pc}$ ]
+The desired direct dependencies of $\pc$, a set of patches.
+
+\item[ $\allpatches$ ]
+The set of all the patches we are dealing with (constructed
+during the update algorithm).
+
 %\item[ $\set E_{\pc}$ ]
 %$ \bigcup_i \pendsof{S_{\pc,i}}{\pc} $.
 %All the ends of $\pc$ in the sources.
@@ -72,6 +79,7 @@ all of its dependencies will be updated.
 
 \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.
 
 \item[ $g : \pc, \Gamma \mapsto \Gamma'$ ]
@@ -80,7 +88,7 @@ of $\pc$.  It is provided with a putative set of direct dependencies
 $\Gamma$ computed as an appropriate merge of the dependencies requested by the
 sources and should return the complete actual set $\Gamma'$ of direct
 dependencies to use.  This allows the specification of any desired
-(acyclic) relation $\hasdirdep$.
+(acyclic) relations $\hasdirdep$ and $\hasdep$.
 
 \end{basedescript}
 
@@ -139,15 +147,17 @@ if available.
 \item For each $i \ldots 1..n$, update our putative direct
 dependencies:
 $$
-\Gamma \assign \text{\bf set-merge}\left(\Gamma, 
- \left[ \begin{cases} 
+\Gamma \assign \text{\bf set-merge}\left[\Gamma, 
+ \left( \begin{cases} 
   M_i \in \pcn :     & \depsreqof{M_i} \\
   M_i \not\in \pcn : & \{ \}
- \end{cases} \right],
+ \end{cases} \right),
  \depsreqof{S_i}
- \right)
+ \right]
 $$
 
+TODO define {\bf set-merge}
+
 \item Finalise our putative direct dependencies
 $
 \Gamma \assign g(\pc, \Gamma)
@@ -165,17 +175,31 @@ inappropriate; a different $g$ could work.)
 
 \end{enumerate}
 
-The results of the ranking phase are:
+\subsection{Results of the ranking phase}
+
+By the end of the ranking phase, we have recorded the following
+information:
 
+\begin{itemize}
+\item
 $ \allpatches, \hasdirdep $ and hence the completion of $\hasdirdep$
 into the partial order $\hasdep$.
 
-For each $\pc$, the base branch starting point commit $W_{\pcn} = W$,
-the direct dependencies $\Gamma_{\pc}$,
+\item
+For each $\pc \in \allpatches$, the base branch starting point commit $W_{\pcn} = W$.
+
+\item
+For each $\pc$,
+the direct dependencies $\Gamma_{\pc}$.
+
+\item
+For each $\pc$,
 the ordered set of base branch sources $\set S_{\pcn} = \set S,
 S_{\pcn,i} = S_i$
 and corresponding merge bases $M_{\pcn,i} = M_i$.
 
+\end{itemize}
+
 \section{Traversal phase}