X-Git-Url: http://git.megacz.com/?p=sbp.git;a=blobdiff_plain;f=TODO;h=bed7ed84443844e07f7e4ab8d7ccb39da684cd35;hp=118520951f00698612b7fb4c1cb1d2465e597861;hb=c8d1c3a25e2bfa9645c4b91d3dde9c4857f636f2;hpb=77d1e5fd29be1ca529e71a4c011f5edea61588e8 diff --git a/TODO b/TODO index 1185209..bed7ed8 100644 --- a/TODO +++ b/TODO @@ -1,71 +1,57 @@ -// priorities are all messy and dont get serialized -// 1. Error messages -// 2. Java MetaGrammar (proof of concept) -// 3. Ivan's MetaGrammar -// 4. Documentation format -// - TIB - -// TODO: better API for interfacing with Java -// TODO: error messages -// TODO: integrate with TIB - -// Element -// Walk -// ParseTable / GSS -// MetaGrammar (necessary/relevant?) -// Tree (cleanup?) -// Union.SubUnion -// Repeat - -// FEATURE: serialization of ParseTable's, generation of Java code -// FEATURE: infer reject elements for literals -// FEATURE: prefer whitespace higher up -// FEATURE: full conjunctive and boolean grammars -// FEATURE: "ambiguity modulo dropped fragments"? can this be checked for statically? eliminated statically? -// - drop stuff during the parsing process (drop nodes) - -// LATER: Element -- parameterize over the input token type? Makes a huge mess... -// LATER: Go back to where Sequence is not an Element? -// - The original motivation for making Sequence "first class" was the fact that -// in order to do associativity right you need to have per-Sequence follow sets - -______________________________________________________________________________ +_____________________________________________________________________________ Immediately - - switch maximal to not-followed-by (~/~) + - do Forest/Tree still need a Region? - - should Union.add() be there? - - should Atom.top() be there? + - evil problems with (x y? z /ws) + - ParseFailed, GSS, Walk, Parser, Sequence, Forest + - copyright notices + - documentation - - fix the location stuff, it's broken - - decent/better error messages + - grammar highlighting? + - comment indentation vs block indentation? + - { and } in
+  - recursive { { foo } }
+
+______________________________________________________________________________
+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?
 
-  - "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
-        if we need to be able to do lift operations on it.
+  - substring parsing for better error messages
 
   - Parameterized LR
   - "Regular Right Part" grammars (NP Chapman, etc)
   - Attribute unification
 
+  - inference of rejections for literals
+  - "prefer whitespace higher up" (?)
+
+  - 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)
@@ -77,11 +63,6 @@ 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
@@ -138,3 +119,23 @@ Later
   - implement Johnstone's algorithm for "reduced, resolved LR
     tables" to eliminate superfluous reductions on
     epsilon-transitions.
+
+______________________________________________________________________________
+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