+// Copyright 2006 all rights reserved; see LICENSE file for BSD-style license
+
package edu.berkeley.sbp.meta;
import edu.berkeley.sbp.util.*;
import edu.berkeley.sbp.*;
public class Grammar {
/**
- * Create a grammar from a parse tree.
- *
- * @param t a tree produced by parsing a grammar using the metagrammar
- * @param s the name of the "start symbol"
- */
- public static Union create(Tree t, String s) {
- return create(t, s, new AnnotationGrammarBindingResolver(MetaGrammarBindings.class));
- }
-
- /**
* Create a grammar from a parse tree and binding resolver
*
* @param t a tree produced by parsing a grammar using the metagrammar
* @param s the name of the "start symbol"
* @param gbr a GrammarBindingResolver that resolves grammatical reductions into tree-node-heads
*/
- public static Union create(Tree t, String s, GrammarBindingResolver gbr) {
- Tree.TreeFunctor<Object,Object> red = (Tree.TreeFunctor<Object,Object>)t.head();
+ public static Union create(Tree t, String s, Grammar.Bindings gbr) {
+ TreeFunctor<Object,Object> red = (TreeFunctor<Object,Object>)t.head();
MetaGrammarBindings.GrammarNode g = (MetaGrammarBindings.GrammarNode)red.invoke(t.children());
return g.build(s, gbr);
}
+
+ public static class Bindings {
+ public Object repeatTag() { return null; }
+ public Sequence createSequence(Production p) {
+ if (p.tag==null) return null;
+ return Sequence.create(p.tag, p.elements, p.drops, false);
+ }
+ }
}