checkpoint

darcs-hash:20051214050748-5007d-ae31b182e3df97c8606513d184a990a90f67b16d.gz

diff --git a/TODO b/TODO
index 1185209..972a801 100644 (file)
--- a/TODO
+++ b/TODO
@@ -1,34 +1,3 @@
-// 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<String> (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<A> -- 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
 
@@ -63,6 +32,13 @@ 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?
+
 ______________________________________________________________________________
 Later
 

diff --git a/src/edu/berkeley/sbp/misc/MetaGrammar.java b/src/edu/berkeley/sbp/misc/MetaGrammar.java
index f408275..0b70878 100644 (file)
--- a/src/edu/berkeley/sbp/misc/MetaGrammar.java
+++ b/src/edu/berkeley/sbp/misc/MetaGrammar.java
@@ -94,14 +94,15 @@ public class MetaGrammar extends ReflectiveWalker {
     public MetaGrammar grammar(Object o, Union[] u, Object x) { return this; }
     public char    _backslash_n() { return '\n'; }
     public char    _backslash_r() { return '\r'; }
-    public String  literal(String s) { return s; }
-    /*
-    public Element literal(String s) {
+    //public String  literal(String s) { return s; }
+
+    public Object literal(String s) {
         Element e = CharToken.string(s);
-        dropAll.add(e);
-        return e;
+        return new MyDrop(e);
+        //dropAll.add(e);
+        //return e;
     }
-    */
+
     public Range     range0(char a)         { return new Range(a, a); }
     public Range     range0(char a, char b) { return new Range(a, b); }
     public Range     range1(char a, char b) { return new Range(a, b); }
@@ -367,6 +368,7 @@ public class MetaGrammar extends ReflectiveWalker {
 
 
 
+
         // DO NOT EDIT STUFF BELOW: IT IS AUTOMATICALLY GENERATED
 new Tree(null, "gram", new Tree[] { new Tree(null, null, new Tree[] { }),
         new Tree(null, "grammar", new Tree[] { new Tree(null, null, new Tree[] { new Tree(null, "::=", new Tree[] { new Tree(null, "sify", new Tree[] { new Tree(null, null, new Tree[] { new Tree(null, "s", new Tree[] { })})}),
@@ -953,3 +955,4 @@ new Tree(null, "gram", new Tree[] { new Tree(null, null, new Tree[] { }),
 
 
 
+