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 d385a55..889e2bc 100644 (file)
--- a/src/edu/berkeley/sbp/misc/MetaGrammar.java
+++ b/src/edu/berkeley/sbp/misc/MetaGrammar.java
@@ -31,9 +31,16 @@ public class MetaGrammar extends ReflectiveWalker {
     private HashMap<String,Union> nt;
     private int anon = 0;
     private String startSymbol;
+    private boolean strings;
 
-    public MetaGrammar() { this("s"); }
-    public MetaGrammar(String s) { done(s); }
+    private Element  set(Range.Set r) { if (strings) throw new Error(); return CharToken.set(r); }
+    private Element  string(String s) { return strings ? StringToken.string(s) : CharToken.string(s); }
+    private Atom     leftBrace()      { return strings ? StringToken.leftBrace : CharToken.leftBrace; }
+    private Atom     rightBrace()     { return strings ? StringToken.rightBrace : CharToken.rightBrace; }
+
+    public MetaGrammar() { this("s", false); }
+    public MetaGrammar(String s) { this(s, false); }
+    public MetaGrammar(String s, boolean strings) { this.strings = strings; done(s); }
     public Union done() { return done("s"); }
     public Union done(String str) {
         Union ret = g;
@@ -86,9 +93,9 @@ public class MetaGrammar extends ReflectiveWalker {
         return nonTerminal("braced"+(anon++),
                            new PreSequence[][] {
                                new PreSequence[] {
-                                   new PreSequence(CharToken.leftBrace),
+                                   new PreSequence(leftBrace()),
                                    p,
-                                   new PreSequence(CharToken.rightBrace)
+                                   new PreSequence(rightBrace())
                                }
                            },
                            false,
@@ -121,7 +128,7 @@ 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 Object    literal(String s) { return new MyDrop(CharToken.string(s)); }
+    public Object    literal(String s) { return new MyDrop(string(s)); }
     public Range     _minus_(char a, char b) { return new Range(a, b); }
     public Range     range(char a)         { return new Range(a, a); }
     public Element   _leftbracket_       (Range[] rr) { return ranges(true, rr); }
@@ -132,19 +139,19 @@ public class MetaGrammar extends ReflectiveWalker {
             for(Range r : rr)
                 if (positive) ret.add(r);
                 else          ret.remove(r);
-        return CharToken.set(ret);
+        return set(ret);
     }
 
-    public static class MyLift {
+    public class MyLift {
         public final String s;
         public MyLift(String s) { this.s = s; }
     }
-    public static class MyDrop {
+    public class MyDrop {
         public final Object o;
         public MyDrop(Object o) { this.o = o; }
     }
 
-    public static class PreSequence {
+    public class PreSequence {
         public PreSequence not(Sequence s) { not.add(s); return this; }
         public PreSequence and(Sequence s) { and.add(s); return this; }
         public final HashSet<Sequence> and  = new HashSet<Sequence>();
@@ -176,7 +183,7 @@ public class MetaGrammar extends ReflectiveWalker {
                     if (oi instanceof MyDrop)      { oi = ((MyDrop)oi).o; drops[j] = true; }
 
                     if (oi==SELF)                    o2[j] = u.new Subset("(("+u+"))", set);
-                    else if (oi instanceof MyLift) { o2[j] = CharToken.string(tag = ((MyLift)oi).s); drops[j] = o.length>1; }
+                    else if (oi instanceof MyLift) { o2[j] = string(tag = ((MyLift)oi).s); drops[j] = o.length>1; }
                     else                             o2[j] = (Element)oi;
 
                     if (MetaGrammar.dropAll.contains(o2[j])) drops[j] = true;