From 7b080eacc0d19ed65c7b16270c647189b9831ecb Mon Sep 17 00:00:00 2001
From: Tony Garnock-Jones <tonygarnockjones@gmail.com>
Date: Mon, 13 Jul 2015 15:56:39 -0400
Subject: [PATCH] Notes

---
 TODO.md | 135 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 135 insertions(+)

diff --git a/TODO.md b/TODO.md
index 9a6fafa..fea80b8 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1 +1,136 @@
 Consider whether a stack or a queue makes most sense for the freelist.
+
+
+Needed by prospect:
+
+ - `pattern->matcher` with `#t`
+
+ - `matcher-project`
+ - `matcher-project/set`
+ - `matcher-project/set/single`
+
+     - many userland uses
+     - one interesting use in `drop-interests` / `drop-patch`, used in `mux-update-stream`
+        - perhaps this can be replaced with a `matcher-step` combination?
+        - no, it'd be a little awkward, because of the trailing close-paren.
+
+ - `matcher-match-value`
+
+     - used to route messages
+     - once to check that noone has asserted the message in the routing table
+     - and once to actually route it
+
+ - `matcher-match-matcher`
+
+     - used in `compute-affected-pids` to project out PIDs on the
+       right (after a step to get past the struct:observe)
+     - used with a combiner that unions in the PIDs on the right
+     - used with a left-short that steps over the close-paren from the struct:observe
+
+ - `matcher-union` with default and with `\vw.#t`
+
+     - used to create cross-level observations in `observe-at-meta` in core
+     - to compute the "cover" of a patch in compute-affected-pids -
+       union of added & removed
+     - used in `apply-patch` and `patch-union` with default combiner
+     - used in `update-interests` and `compose-patch` with a combiner
+       that ignores the structure of the ok() value
+     - (used in `unapply-patch`, which is not used)
+
+ - `matcher-step` (for removing open-paren and observation marks and
+   skipping the corresponding close-paren)
+
+     - used in `biased-intersection` and `compute-affected-pids` to
+       skip struct:observe
+
+ - `matcher-relabel`
+
+     - used throughout to replace ok() leaf values.
+
+ - `matcher-subtract` with default, `\vw.#f`, `add-combiner` and `rem-combiner`
+
+     - used with always-false in `limit-patch`, `compose-patch` and
+       `update-interests`, ignoring the ok() values
+     - used with default in `compute-patch` (and in `limit-patch/routing-table`, which is not used)
+     - used with both `add-combiner` and `rem-combiner` in `compute-aggregate-patch`
+     - used with default in `apply-patch`
+     - (used in `unapply-patch`, which is not used)
+
+ - `matcher-intersect` with `\vw.v`, `\vw.v∩w`, and `\vw.#t` with a left-short argument.
+
+     - used in `limit-patch` in a way that's tantamount to an explicit simultaneous relabelling
+     - used with an always-true combiner in `biased-intersection`
+     - (used in `limit-patch/routing-table`, which is unused)
+
+
+    digraph Dependencies {
+		graph [rankdir=LR];
+
+		// matcher
+		subgraph xcluster_union {
+		  unionUnit;
+		  unionPIDs;
+	    }
+        project;
+        matchValue;
+        matchMatcher;
+        step;
+        relabel;
+		subgraph xcluster_subtract {
+		  subtractUnit;
+          subtractPIDs;
+		  subtractCustom;
+        }
+		subgraph xcluster_intersect {
+		  intersectAsymmetric;
+		  intersectUnit;
+        }
+
+        // patch
+		// composePatch -> subtractUnit;
+		// composePatch -> unionUnit;
+		// computePatch -> subtractUnit; // I guess?
+		// stripInterests -> relabel;
+		// stripPatch -> stripInterests;
+		applyPatch -> subtractPIDs;
+		applyPatch -> unionPIDs;
+		biasedIntersection -> intersectUnit;
+		biasedIntersection -> step;
+		computeAggregatePatch -> subtractCustom;
+		labelInterests -> relabel;
+		limitPatch -> intersectAsymmetric;
+		limitPatch -> subtractUnit;
+		patchUnion -> unionUnit;
+		updateInterests -> subtractUnit;
+		updateInterests -> unionUnit;
+        dropInterests -> project;
+        labelPatch -> labelInterests;
+
+        // mux
+		computeAffectedPIDs -> matchMatcher;
+		computeAffectedPIDs -> step;
+		computeAffectedPIDs -> unionUnit;
+		messageRouting -> matchValue;
+		muxUpdateStream -> applyPatch;
+		muxUpdateStream -> biasedIntersection;
+		muxUpdateStream -> computeAffectedPIDs;
+		muxUpdateStream -> computeAggregatePatch;
+		muxUpdateStream -> dropInterests;
+		muxUpdateStream -> labelPatch;
+		muxUpdateStream -> limitPatch;
+		muxUpdateStream -> patchUnion;
+
+	    // core
+		observeAtMeta -> union;
+
+	    // user code
+		userCode -> project;
+        userCode -> observeAtMeta;
+
+        // semantics
+        semantics -> muxUpdateStream;
+		semantics -> messageRouting;
+		groundVM -> applyPatch;
+		groundVM -> labelPatch;
+		demandMatcher -> updateInterests;
+    }