X-Git-Url: http://git.megacz.com/?p=sbp.git;a=blobdiff_plain;f=TODO;h=14b121ef1b908a4bb4b0d451f0f23c29814307b7;hp=14e38b529ab09af3314873a49e1848fb74f001ef;hb=5964a1161340a16d7dea471372737f2474576ceb;hpb=574d2f85990e11f0a45e9028fbadf08aaedfd93a

diff --git a/TODO b/TODO
index 14e38b5..14b121e 100644
--- a/TODO
+++ b/TODO
@@ -1,48 +1,37 @@
 _____________________________________________________________________________
 Immediately
 
-  - simplify metagrammar => go to top-down rewriting => finalize metagrammar and rdp-op's
+  - Repeat, Sequence, Tree
+  - simplify Forest (considerably)
 
-  - What is our use model?
-    - Parse, attribute, unify       (ag)
-    - Parse, transform tree, walk   (rdp)
-    - Parse, walk
-    - cascading tree rewrites
-
-      ==> use the middle formalism "for now" and in meta.g; layer others
-          on top of it
-
-  - Lay down the law on the different kinds of Sequence productions
-    and how they work.
-
-     => mydrop
-     => mylift
-
-  - whitespace-in-braces?
-  - Deal with the problem of zero-rep productions and whitespace insertion
-
-  - switch maximal to not-followed-by (~/~)
+  - decent/better error messages
+      - fix the location stuff, it's broken
 
-  - should Union.add() be there?
-  - should Atom.top() be there?
+  - copyright notices
+  - documentation
 
-  - fix the location stuff, it's broken
-  - decent/better error messages
+______________________________________________________________________________
+v1.1
 
+  - finalize metagrammar and rdp-op's
   - write some grammars
       - Java grammar
       - TeX (math?)
       - URL (RFC)
       - RFC2822 (email message/headers)
-      - Wiki grammar
+  - clean up the whole Walk situation (?)
+
 
 ______________________________________________________________________________
 Soon
 
-  - clean up the whole Walk situation
+  - serialization of parse tables
 
-  - cleaner solution to "maximal"?
+  - "ambiguity modulo dropped fragments"?
+       - can this be checked statically?
+       - eliminated statically?
 
+  - substring parsing for better error messages
   - "lift" cases:
       - right now I can only lift the last child in a forest...  begs
         the question of what the right representation for Forests is
@@ -52,16 +41,18 @@ Soon
   - "Regular Right Part" grammars (NP Chapman, etc)
   - Attribute unification
 
-  - serialization of parse tables
   - inference of rejections for literals
   - "prefer whitespace higher up" (?)
-  - "ambiguity modulo dropped fragments"?
-       - can this be checked statically?
-       - eliminated statically?
+
+  - Labeled edges on trees (associate a label with each slot in the
+    child array in Forest.Body?  might make equality tough) --
+    equivalent to Feature Structures.  Colon-labeling.
 
 ______________________________________________________________________________
 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 +64,6 @@ 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
@@ -140,3 +126,17 @@ Neat Ideas
 
   - Rekers & Koorn note that GLR Substring Parsing can be used to do
     really elegant and generalized "autocompletion".
+
+
+______________________________________________________________________________
+Ideas for the Future
+
+- Incremental parse table construction
+- "lazy GLR" and "lazy trees" -> language with first-class CF matching
+    - perhaps linear boolean grammars instead? (linear time, quad space)
+- Forest parsing => chained parsers
+- unification parsing, attributes, etc
+- RRP grammars?
+- Take another stab at maximal-match?  Nonterminal not-followed-by is
+  too strong.
+- Error recovery based on substring parsing