checkpoint

[sbp.git] / src / edu / berkeley / sbp / misc / MetaGrammar.java

diff --git a/src/edu/berkeley/sbp/misc/MetaGrammar.java b/src/edu/berkeley/sbp/misc/MetaGrammar.java
index 378a53c..bdb8096 100644 (file)
--- a/src/edu/berkeley/sbp/misc/MetaGrammar.java
+++ b/src/edu/berkeley/sbp/misc/MetaGrammar.java
@@ -7,6 +7,22 @@ import java.io.*;
 
 public class MetaGrammar extends StringWalker {
 
+    /** an atom which tracks the possible tokenset of some element, provided that element can only match single-token sequences */
+    static class Infer<T extends Input> extends Atom<T> {
+        private final Element e;
+        public Infer(Element e) { this.e = e; }
+        public Topology<T> top() { return (Topology<T>)toAtom(e); }
+        public String toString() { return e.toString(); }
+    }
+
+    /** an atom which tracks the inverse of some other atom */
+    static class Invert<T extends Input> extends Atom<T> {
+        private final Atom<T> a;
+        public Invert(Atom<T> a) { this.a = a; }
+        public Topology<T> top() { return a.complement(); }
+        public String toString() { return "~"+a; }
+    }
+
     public static class Hack<T extends Input> extends Atom<T> {
         private final Atom<T> a;
         static final Topology leftright = CharRange.rightBrace.union(CharRange.leftBrace);
@@ -115,14 +131,14 @@ public class MetaGrammar extends StringWalker {
         if      ("\\n".equals(head)) return new Character('\n');
         else if ("\\r".equals(head)) return new Character('\r');
         else if ("grammar".equals(head)) { for(Tree<String> t : tree.children()) walk(t); return this; }
-        else if ("*".equals(head))   return Repeat.many0((Element)walk(tree.child(0)), repeatTag());
-        else if ("+".equals(head))   return Repeat.many1((Element)walk(tree.child(0)), repeatTag());
-        else if ("+/".equals(head))  return Repeat.many1((Element)walk(tree.child(0)), (Element)walk(tree.child(1)), repeatTag());
-        else if ("*/".equals(head))  return Repeat.many0((Element)walk(tree.child(0)), (Element)walk(tree.child(1)), repeatTag());
-        else if ("++/".equals(head)) return Repeat.maximal1((Element)walk(tree.child(0)), (Element)walk(tree.child(1)), repeatTag());
-        else if ("**".equals(head))  return Repeat.maximal0((Element)walk(tree.child(0)), repeatTag());
-        else if ("++".equals(head))  return Repeat.maximal1((Element)walk(tree.child(0)), repeatTag());
-        else if ("?".equals(head))   return Repeat.maybe((Element)walk(tree.child(0)), repeatTag());
+        else if ("*".equals(head))   return Sequence.many0((Element)walk(tree.child(0)), repeatTag());
+        else if ("+".equals(head))   return Sequence.many1((Element)walk(tree.child(0)), repeatTag());
+        else if ("+/".equals(head))  return Sequence.many1((Element)walk(tree.child(0)), (Element)walk(tree.child(1)), repeatTag());
+        else if ("*/".equals(head))  return Sequence.many0((Element)walk(tree.child(0)), (Element)walk(tree.child(1)), repeatTag());
+        else if ("++/".equals(head)) return Sequence.maximal1((Element)walk(tree.child(0)), (Element)walk(tree.child(1)), repeatTag());
+        else if ("**".equals(head))  return Sequence.maximal0((Element)walk(tree.child(0)), repeatTag());
+        else if ("++".equals(head))  return Sequence.maximal1((Element)walk(tree.child(0)), repeatTag());
+        else if ("?".equals(head))   return Sequence.maybe((Element)walk(tree.child(0)), repeatTag());
         else if ("!".equals(head))   { Element e = (Element)walk(tree.child(0)); dropAll.add(e); return e; }
         else if ("&".equals(head))   return ((Sequence)walk(tree,0)).and(sequence(walk(tree, 1), true));
         else if ("and".equals(head)) return ((Sequence)walk(tree,0)).and(sequence(walk(tree, 1), true));
@@ -153,7 +169,7 @@ public class MetaGrammar extends StringWalker {
         else if ("->".equals(head)) { PreSequence p = (PreSequence)walk(tree, 0); p.noFollow = (Element)walk(tree, 1); return p; }
         else if ("/".equals(head)) return ((PreSequence)walk(tree, 0)).sparse((Element)walk(tree, 1));
         else if (" /".equals(head)) return ((PreSequence)walk(tree, 0)).sparse((Element)walk(tree, 1));
-        else if ("~".equals(head)) return new Hack(new Atom.Invert(new Atom.Infer((Element)walk(tree, 0))));
+        else if ("~".equals(head)) return new Hack(new Invert(new Infer((Element)walk(tree, 0))));
         else if ("ps".equals(head)) return new PreSequence((Object[])walk(tree,0), null);
         else if (":".equals(head)) {
             String s = string(tree.child(0));
@@ -300,7 +316,7 @@ public class MetaGrammar extends StringWalker {
             Element[] expansion = o2;
             Sequence ret = null;
             if (dropAll || lame) ret = Sequence.drop(expansion, lame);
-            else if (unwrap)    ret = new Sequence.Unwrap(expansion, repeatTag(), drops);
+            else if (unwrap)    ret = Sequence.unwrap(expansion, repeatTag(), drops);
             else if (keeping || tag!=null) ret = Sequence.rewritingSequence(tag, expansion, labels, drops);
             else {
                 int idx = -1;
@@ -314,7 +330,7 @@ public class MetaGrammar extends StringWalker {
             for(Sequence s : and) ret = ret.and(s);
             for(Sequence s : not) ret = ret.not(s);
             set.add(ret);
-            if (this.noFollow != null) ret.noFollow = new Atom.Invert(new Atom.Infer(this.noFollow));
+            if (this.noFollow != null) ret.noFollow = new Invert(new Infer(this.noFollow));
             return ret;
         }
     }
@@ -510,6 +526,7 @@ public class MetaGrammar extends StringWalker {
 
 
 
+
         // DO NOT EDIT STUFF BELOW: IT IS AUTOMATICALLY GENERATED
 new edu.berkeley.sbp.Tree(null, "grammar", new edu.berkeley.sbp.Tree[] { new edu.berkeley.sbp.Tree(null, null, new edu.berkeley.sbp.Tree[] { new edu.berkeley.sbp.Tree(null, "=", new edu.berkeley.sbp.Tree[] { new edu.berkeley.sbp.Tree(null, null, new edu.berkeley.sbp.Tree[] { new edu.berkeley.sbp.Tree(null, "s", new edu.berkeley.sbp.Tree[] { })}),
         new edu.berkeley.sbp.Tree(null, null, new edu.berkeley.sbp.Tree[] { new edu.berkeley.sbp.Tree(null, null, new edu.berkeley.sbp.Tree[] { new edu.berkeley.sbp.Tree(null, "psx", new edu.berkeley.sbp.Tree[] { new edu.berkeley.sbp.Tree(null, "ps", new edu.berkeley.sbp.Tree[] { new edu.berkeley.sbp.Tree(null, null, new edu.berkeley.sbp.Tree[] { new edu.berkeley.sbp.Tree(null, "!", new edu.berkeley.sbp.Tree[] { new edu.berkeley.sbp.Tree(null, "nonTerminal", new edu.berkeley.sbp.Tree[] { new edu.berkeley.sbp.Tree(null, null, new edu.berkeley.sbp.Tree[] { new edu.berkeley.sbp.Tree(null, "w", new edu.berkeley.sbp.Tree[] { }),
@@ -1170,3 +1187,4 @@ new edu.berkeley.sbp.Tree(null, "grammar", new edu.berkeley.sbp.Tree[] { new edu
 
 
 
+