import java.util.*;
import java.io.*;
-public class MetaGrammar extends ReflectiveWalker {
+public class MetaGrammar extends StringWalker {
public static Union make() throws Exception {
return ((MetaGrammar)new MetaGrammar().walk(meta)).done();
return n;
}
- public Object _backslash__leftbrace_(String s) { return SELF; }
- public Object _leftbrace_(PreSequence p) {
- return nonTerminal("braced"+(anon++),
- new PreSequence[][] {
- new PreSequence[] {
- new PreSequence(new Element[] { leftBrace(),
- p.buildUnion(),
- rightBrace()
- })
- }
- },
- false,
- false);
- }
-
- public PreSequence _equals__greater_(PreSequence p, String tag) { p.tag = tag; return p; }
-
- public PreSequence ps(Object[] o) { return new PreSequence(o); }
- public PreSequence ps2(Object[] o1, String s, Object[] o2) {
- if (o1==null) o1 = new Object[0];
- if (o2==null) o2 = new Object[0];
- Object[] o3 = new Object[o1.length + o2.length + 1];
- System.arraycopy(o1, 0, o3, 0, o1.length);
- o3[o1.length] = string(s);
- System.arraycopy(o2, 0, o3, o1.length+1, o2.length);
- PreSequence ret = new PreSequence(o3, s);
- ret.drops[o1.length] = o3.length>1;
+ public String string(Iterable<Tree<String>> children) {
+ String ret = "";
+ for(Tree<String> t : children) ret += string(t);
return ret;
}
- public PreSequence _slash_(PreSequence p, Object sep) { return p.sparse(sep); }
-
public String string(Tree<String> tree) {
String ret = "";
if (tree.head()!=null) ret += tree.head();
- for(Tree<String> t : tree.children()) ret += string(t);
+ ret += string(tree.children());
return ret;
}
else if ("**".equals(head)) return Repeat.maximal(Repeat.many0((Element)walk(tree.child(0))));
else if ("++".equals(head)) return Repeat.maximal(Repeat.many1((Element)walk(tree.child(0))));
else if ("?".equals(head)) return Repeat.maybe((Element)walk(tree.child(0)));
- else if ("&".equals(head)) return ((PreSequence)walk(tree,0)).and(new PreSequence((Element[])Reflection.lub((Object[])walk(tree, 1)), null).buildSequence(null, true, false));
- else if ("&~".equals(head)) return ((PreSequence)walk(tree,0)).not(new PreSequence((Element[])Reflection.lub((Object[])walk(tree, 1)), null).buildSequence(null, true, false));
+ else if ("&".equals(head))
+ return ((PreSequence)walk(tree,0)).and(new PreSequence((Element[])Reflection.lub((Object[])walk(tree, 1)), null).buildSequence(null, true, false));
+ else if ("&~".equals(head))
+ return ((PreSequence)walk(tree,0)).not(new PreSequence((Element[])Reflection.lub((Object[])walk(tree, 1)), null).buildSequence(null, true, false));
else if ("epsilon".equals(head)) return Union.epsilon;
else if ("()".equals(head)) return Union.epsilon;
else if (")".equals(head)) return SELF;
else if ("::=".equals(head)) return nonTerminal(string(tree.child(0)), (PreSequence[][])walk(tree, 1), false, false);
else if ("!::=".equals(head)) return nonTerminal(string(tree.child(0)), (PreSequence[][])walk(tree, 1), false, true);
else if ("(".equals(head)) return nonTerminal("anon"+(anon++), (PreSequence[][])walk(tree, 0), false, false);
+ else if ("literal".equals(head)) { Element ret = string(string(tree.child(0))); dropAll.add(ret); return ret; }
+ else if ("-".equals(head)) return new Range(walk(tree, 0).toString().charAt(0), walk(tree,1).toString().charAt(0));
+ else if ("range".equals(head)) return new Range(walk(tree, 0).toString().charAt(0), walk(tree,0).toString().charAt(0));
+ else if ("gram".equals(head)) return walk(tree, 1);
+ else if ("=>".equals(head)) { PreSequence p = (PreSequence)walk(tree, 0); p.tag = string(tree.child(1)); return p; }
+ else if ("/".equals(head)) return ((PreSequence)walk(tree, 0)).sparse((Element)walk(tree, 1));
+ else if ("ps".equals(head)) return new PreSequence((Element[])walk(tree, 0));
+ else if ("ps2".equals(head)) {
+ Object[] o1 = (Object[])walk(tree, 0);
+ String s = string(tree.child(1));
+ Object[] o2 = (Object[])walk(tree, 2);
+ if (o1==null) o1 = new Object[0];
+ if (o2==null) o2 = new Object[0];
+ Object[] o3 = new Object[o1.length + o2.length + 1];
+ System.arraycopy(o1, 0, o3, 0, o1.length);
+ o3[o1.length] = string(s);
+ System.arraycopy(o2, 0, o3, o1.length+1, o2.length);
+ PreSequence ret = new PreSequence(o3, s);
+ ret.drops[o1.length] = o3.length>1;
+ return ret;
+ } else if ("[".equals(head) || "[~".equals(head)) {
+ boolean positive = "[".equals(head);
+ Range[] rr = (Range[])walk(tree, 0);
+ Range.Set ret = positive ? new Range.Set() : new Range.Set(new Range(true, true));
+ if (rr != null)
+ for(Range r : rr)
+ if (positive) ret.add(r);
+ else ret.remove(r);
+ return set(ret);
+ }
else return super.walk(tree);
}
- public Object gram(Object o, Object g, Object o2) { return g; }
- public Element literal(String s) { Element ret = string(s); dropAll.add(ret); return ret; }
- 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); }
- public Element _leftbracket__tilde_(Range[] rr) { return ranges(false, rr); }
- public Element ranges(boolean positive, Range[] rr) {
- Range.Set ret = positive ? new Range.Set() : new Range.Set(new Range(true, true));
- if (rr != null)
- for(Range r : rr)
- if (positive) ret.add(r);
- else ret.remove(r);
- return set(ret);
+
+ public Object walk(String tag, Object[] argo) {
+ if (argo.length==0) return super.walk(tag, argo);
+ if (argo==null) return tag;
+ if (tag==null || "".equals(tag)) return argo;
+ return super.walk(tag, argo);
}
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