TODO update.

TODO

@@ -28,27 +28,12 @@
 * standard library: define "%public %inline epsilon: {}", which allows using
   "epsilon" as a marker for an empty right-hand side.
 
-* Inspired by BtYacc inherited attributes, which are just syntactic sugar
-  for embedded semantic actions and accesses to the stack at $0, $-1, etc.
-  In other words, a way of using the LR stack for parameter passing.
-  Could Menhir offer something like this? (in a safe way)
-  Every non-terminal symbol would have a "stack type" (a hypothesis about
-  the types of the semantic values on the stack). By default, empty.
-  If non-empty, introduces names for the semantic values.
-  e.g.
-    list<sum>: /* empty */                  { sum }
-             | i = INT sum' = list<sum + i> { sum' }
-  This allows left-to-right-carried state in a list, even though the list
-  is right-recursive, and without using mutable state.
-  (But is that really interesting?)
-  Desugared to:
-    list: /* assumes an integer sum is on the stack */
-      sum = POP { sum }
-    | sum = POP i = INT PUSH<sum + i> sum' = list { sum' }
-  One could read "POP" as a normal nonterminal symbol (of ocaml type int)
-  and read "PUSH" as a primitive embedded action that reduces the empty
-  word to a POP symbol.
-  So if we have embedded actions, we can encode inherited attributes.
+* Implement $0, $-1, etc.
+    with and without --infer, must be type-safe
+    in the code and table back-ends
+  On top of that, it is easy to implement mid-rule actions (à la Bison).
+  On top of that, it should be easy to implement inherited attributes (à la BtYacc).
+    again, should be type-safe
 
 * Installation problems.
   - put menhirLib.{ml,mli} in a different directory;