added code to check for created-by-empty-reduction

[sbp.git] / TODO

diff --git a/TODO b/TODO
index 14e38b5..fd55d0b 100644 (file)
--- a/TODO
+++ b/TODO
@@ -1,47 +1,41 @@
 _____________________________________________________________________________
 Immediately
 
-  - simplify metagrammar => go to top-down rewriting => finalize metagrammar and rdp-op's
+  - Performance
 
-  - What is our use model?
-    - Parse, attribute, unify       (ag)
-    - Parse, transform tree, walk   (rdp)
-    - Parse, walk
-    - cascading tree rewrites
+     - Forest: keep() and valid() -- can we do this with states
+       rather than subtrees?
 
-      ==> use the middle formalism "for now" and in meta.g; layer others
-          on top of it
+     - hash Long->long: it's all bogus
 
-  - Lay down the law on the different kinds of Sequence productions
-    and how they work.
+  * pick back up cleaning up end of Parser.java (Reduction)
 
-     => mydrop
-     => mylift
+  - [more] sensible tree-printout
 
-  - whitespace-in-braces?
-  - Deal with the problem of zero-rep productions and whitespace insertion
+  - revamp Tib.Block (do it all in the parser using indent/dedent?)
 
-  - switch maximal to not-followed-by (~/~)
+  - more natural phrasing of metagrammar?
+  - finalize metagrammar and rdp-op's
 
   - should Union.add() be there?
   - should Atom.top() be there?
 
-  - fix the location stuff, it's broken
   - decent/better error messages
+      - fix the location stuff, it's broken
 
   - write some grammars
       - Java grammar
       - TeX (math?)
       - URL (RFC)
       - RFC2822 (email message/headers)
-      - Wiki grammar
+
 
 ______________________________________________________________________________
 Soon
 
-  - clean up the whole Walk situation
+  - substring parsing for better error messages
 
-  - cleaner solution to "maximal"?
+  - clean up the whole Walk situation
 
   - "lift" cases:
       - right now I can only lift the last child in a forest...  begs
@@ -62,6 +56,8 @@ Soon
 ______________________________________________________________________________
 Later
 
+  - Partly-Linear-PATR? (O(n^6) unification grammar)
+
   - Implement a k-token peek buffer (for each state, see if it "dead
     ends" during the next k Phases based solely on state -- ignoring
     result SPPF)
@@ -73,11 +69,6 @@ Later
     nodes which are transient in the sense that they have only one
     eligible reduction?
 
-  - Implement "GLR syntactic predicates" -- the ability to do
-    arbitrary lookahead (ie "followed-by" and "not-followed-by" for
-    arbitrary patterns).  This enables generalized longest-match and
-    lets us drop the Maximal hack.
-
   - Re-read Rekers, particularly the stuff on optimal sharing
 
   - Isolate the Element objects from Parse.Table/GSS so we can move