Search an event's keyed lists by a key set and lists by fingers, add by key in one descent, and loop without recursion (020)

- An event's list keyed by a number keeps its keys beside its tree: bits
  while they are small whole numbers, else an open-addressing table;
  has() reads only that, and inserts, removes, key changes, their undoing
  and clears keep it.
- Each thread keeps fingers on the last four leaves it read (list id and
  version must match): reads by position and searches by key that land in
  them do not descend.
- pure_list_add finds a key's place and inserts there in one descent; a
  stored keyed list's appends take it too, journaled as inserts.
- Child searches count over the whole guide; item fields know at load
  whether they are text; loops run on a stack of loop records, not by
  recursion; module-list.c builds at -O3.
- test-module: the key set and fingers answer as a model at every step
  (bits to table, removes inside runs, undone changes, clears, shares),
  and a stored keyed list's adds replay from its journal.

1 files changed, 2 insertions, 1 deletions

diff --git a/core/module.h b/core/module.h
index c5b7ba0..80d4460 100644
--- a/core/module.h
+++ b/core/module.h
@@ -198,7 +198,8 @@ const char *pure_fault_name(PureFault);
 
 /* plan, shape and range are the runtime's, set at load: a fold whose block
  * has a form for every instruction that works on a leaf of its list at once
- * runs so (plan), one in a column may be answered for every row from one
+ * runs so (plan; for an item's field, or a keyed list's key, read or set:
+ * whether it is a text), one in a column may be answered for every row from one
  * pass over its list (shape: its PureShape + 1), and a fold or a walk whose
  * test bounds a keyed list's key reads only the items in bounds (range: its
  * PureRange + 1). */