1 package edu.berkeley.sbp.misc;
2 import edu.berkeley.sbp.util.*;
3 import edu.berkeley.sbp.*;
4 import edu.berkeley.sbp.chr.*;
6 import java.lang.annotation.*;
7 import java.lang.reflect.*;
12 public static boolean harsh = false;
14 public static void main(String[] s) throws Exception {
16 ReflectiveMeta m = new ReflectiveMeta();
17 Tree<String> res = new CharParser(MetaGrammar.make()).parse(new FileInputStream(s[0])).expand1();
18 MetaGrammar.Meta.MetaGrammarFile mgf = m.new MetaGrammarFile(res);
19 MetaGrammar.BuildContext bc = new MetaGrammar.BuildContext(mgf);
21 Union meta = mgf.get("s").build(bc);
22 Tree t = new CharParser(meta).parse(new FileInputStream(s[1])).expand1();
24 Union u = Demo.make(t, "s");
27 System.err.println("== parsing with parsed grammar =================================================================================");
28 t = new CharParser((Union)u).parse(new FileInputStream(s[1])).expand1();
29 System.out.println(t.toPrettyString());
31 System.err.println("== parsing with parsed-parsed grammar ==========================================================================");
32 t = new CharParser(new Context(t, m).build()).parse(new FileInputStream(s[1])).expand1();
33 System.out.println(t.toPrettyString());
36 public static class ReflectiveMetaPlain extends ReflectiveMeta {
37 public Object repeatTag() { return null; }
38 public Sequence tryResolveTag(String tag, String nonTerminalName, Element[] els, Object[] labels, boolean[] drops) {
40 public Sequence resolveTag(String tag, String nonTerminalName, Element[] els, Object[] labels, boolean[] drops) {
41 return Sequence.rewritingSequence(tag, els, labels, drops);
45 public static class ReflectiveMeta extends MetaGrammar.Meta {
46 private final Class _cl;
47 private final Class[] _inner;
48 public ReflectiveMeta() {
57 MG.NonTerminalReference.class,
58 MG.StringLiteral.class,
63 public ReflectiveMeta(Class c, Class[] inner) {
67 private boolean match(Method m, String s) { return match(m.getAnnotation(tag.class), null, s); }
68 private boolean match(tag t, Class c, String s) {
69 if (t==null) return false;
70 if (t.value().equals(s)) return true;
71 if (c != null && t.equals("") && c.getSimpleName().equals(s)) return true;
74 private boolean match(nonterminal t, Class c, String s) {
75 if (t==null) return false;
76 if (t.value().equals(s)) return true;
77 if (c != null && t.equals("") && c.getSimpleName().equals(s)) return true;
80 private boolean match(Class c, String s, String nonTerminalName) {
81 if (match((tag)c.getAnnotation(tag.class), c, s)) return true;
82 if (match((nonterminal)c.getAnnotation(nonterminal.class), c, nonTerminalName)) return true;
85 public boolean match(Constructor con, String s, String nonTerminalName) {
86 Class c = con.getDeclaringClass();
87 if (match((tag)con.getAnnotation(tag.class), null, s)) return true;
88 if (match((nonterminal)con.getAnnotation(nonterminal.class), c, s)) return true;
91 public Object repeatTag() {
92 return new Tree.ArrayBuildingTreeFunctor<Object>();
94 public Sequence tryResolveTag(String tag, String nonTerminalName, Element[] els, Object[] labels, boolean[] drops) {
95 Production p = new Production(tag, nonTerminalName, els, labels, drops);
96 for(Method m : _cl.getMethods())
97 if (new TargetMethod(m).isCompatible(p))
98 return new TargetMethod(m).makeSequence(p);
100 for(Constructor con : c.getConstructors())
101 if (new TargetConstructor(con).isCompatible(p))
102 return new TargetConstructor(con).makeSequence(p);
103 for(Class c : _inner)
104 if (new TargetClass(c).isCompatible(p))
105 return new TargetClass(c).makeSequence(p);
108 public Sequence resolveTag(String tag, String nonTerminalName, Element[] els, Object[] labels, boolean[] drops) {
109 Sequence ret = tryResolveTag(tag, nonTerminalName, els, labels, drops);
110 if (ret != null) return ret;
111 String message = "could not find a Java method/class/ctor matching tag \""+tag+
112 "\", nonterminal \""+nonTerminalName+"\" with " + els.length + " arguments";
114 throw new RuntimeException(message);
116 System.err.println(message);
117 return Sequence.rewritingSequence(tag, els, labels, drops);
124 * Constructors, classes, and methods with this attribute will
125 * match every production of the nonterminal called "value()"
126 * that is arg-compatible. If value() is undefined, then the
127 * class/constructor/method name is used.
129 @Retention(RetentionPolicy.RUNTIME) public static @interface nonterminal { String value() default ""; }
131 @Retention(RetentionPolicy.RUNTIME) public static @interface raw { }
134 * Constructors, classes, and methods with this attribute will
135 * match every tree tagged with "value()" that is arg-compatible.
136 * If value() is undefined, then the class/constructor/method
139 @Retention(RetentionPolicy.RUNTIME) public static @interface tag { String value() default ""; }
142 * If any parameter to a method or field in a class has a named
143 * arg-tag, that parameter/field matches the child of the tree
144 * which either has that label or else is a reference to a
145 * nonterminal with the corresponding name.
147 * The remaining non-named arg-tags match the remaining children
148 * of the tree in sequential order.
150 * If any arg-tagged parameters/fields remain, the match fails.
151 * If there were no arg-tagged parameters-fields, it is as if all
152 * of them were non-named and arg-tagged.
154 * A method/constructor is arg-compatible if all of its arguments
155 * are arg-compatible.
157 * A class is arg-compatible if all of its fields are
158 * arg-compatible, or if one of its constructors is arg-compatible.
161 @Retention(RetentionPolicy.RUNTIME) public static @interface arg { String value() default ""; }
163 public static class Production {
165 public String nonTerminal;
166 public Object[] labels;
167 public boolean[] drops;
168 public Element[] elements;
169 public int count = 0;
170 public Production(String tag, String nonTerminal, Element[] elements, Object[] labels, boolean[] drops) {
172 this.elements = elements;
173 this.nonTerminal = nonTerminal;
174 this.labels = labels;
176 for(int i=0; i<drops.length; i++)
182 public static abstract class Target {
183 public abstract String getName();
184 public abstract tag getTag();
185 public abstract nonterminal getNonTerminal();
186 public abstract int[] buildSequence(Production p);
187 public boolean isCompatible(Production p) {
190 (t.value().equals(p.tag) ||
191 (t.value().equals("") && getName().equals(p.tag))))
192 return buildSequence(p)!=null;
194 nonterminal n = getNonTerminal();
196 (n.value().equals(p.nonTerminal) ||
197 (n.value().equals("") && getName().equals(p.nonTerminal))))
198 return buildSequence(p)!=null;
202 public int[] buildSequence(Production p, String[] names, arg[] argtags) {
204 for(int i=0; i<argtags.length; i++)
205 if (argtags[i] != null)
208 // FIXME: can be smarter here
209 if (names.length==p.count) {
210 int[] ret = new int[p.count];
211 for(int i=0; i<p.count; i++) ret[i] = i;
213 } else if (argTagged==p.count) {
214 int[] ret = new int[argtags.length];
216 for(int i=0; i<argtags.length; i++)
217 ret[i] = argtags[i]==null ? -1 : (j++);
223 public Sequence makeSequence(Production p) {
224 return Sequence.rewritingSequence(new TargetReducer(p, buildSequence(p), "reducer-"+this), p.elements, p.labels, p.drops);
226 public abstract Object plant(Object[] fields);
227 public boolean isRaw() { return false; }
228 public Object invokeRaw(Iterable<Tree<Object>> t) { return null; }
229 public class TargetReducer implements Tree.TreeFunctor<Object,Object> {
230 private Production p;
233 public TargetReducer(Production p, int[] map, String name) {
238 public String toString() { return name; }
239 public Object invoke(Iterable<Tree<Object>> t) {
240 if (isRaw()) return invokeRaw(t);
241 ArrayList ret = new ArrayList();
243 if (tc.head() != null && tc.head() instanceof Functor)
244 ret.add(((Tree.TreeFunctor<Object,Object>)tc.head()).invoke(tc.children()));
245 else if (tc.numChildren() == 0)
248 System.err.println("FIXME: don't know what to do about " + tc);
252 System.err.println("input tree: " + t);
253 Object[] o = (Object[])ret.toArray(new Object[0]);
255 for(int i=0; i<map.length; i++) max = Math.max(map[i], max);
256 Object[] o2 = new Object[max+1];
257 for(int i=0; i<o.length; i++) o2[map[i]] = o[i];
263 public static class TargetClass extends Target {
264 public final Class _class;
265 public TargetClass(Class _class) { this._class = _class; }
266 public String getName() { return _class.getSimpleName(); }
267 public tag getTag() { return (tag)_class.getAnnotation(tag.class); }
268 public nonterminal getNonTerminal() { return (nonterminal)_class.getAnnotation(nonterminal.class); }
269 public String toString() { return _class.getSimpleName(); }
270 public int[] buildSequence(Production p) {
271 Field[] f = _class.getDeclaredFields();
272 String[] names = new String[f.length];
273 arg[] argtags = new arg[f.length];
274 for(int i=0; i<f.length; i++) {
275 names[i] = f[i].getName();
276 argtags[i] = f[i].getAnnotation(arg.class);
278 int[] ret = buildSequence(p, names, argtags);
279 if (ret!=null) return ret;
280 for(Constructor c : _class.getConstructors())
281 if (new TargetConstructor(c).buildSequence(p)!=null)
282 return new TargetConstructor(c).buildSequence(p);
285 public Object plant(Object[] fields) {
287 Object ret = _class.newInstance();
288 Field[] f = _class.getFields();
290 for(int i=0; i<f.length; i++) {
291 Object tgt = Reflection.lub(fields[i]);
292 if (f[i].getType() == String.class) tgt = stringify(tgt);
294 tgt = coerce(tgt, f[i].getType());
295 System.err.println("setting a " + f[i].getType().getName() + " to " + Reflection.show(tgt));
299 } catch (Exception e) {
301 throw new RuntimeException(e);
306 public static String stringify(Object o) {
307 if (o==null) return "";
308 if (!(o instanceof Object[])) return o.toString();
309 Object[] arr = (Object[])o;
310 StringBuffer ret = new StringBuffer();
311 for(int i=0; i<arr.length; i++)
313 return ret.toString();
316 public static class TargetConstructor extends Target {
317 public final Constructor _ctor;
318 public TargetConstructor(Constructor _ctor) { this._ctor = _ctor; }
319 public String getName() { return _ctor.getName(); }
320 public tag getTag() { return (tag)_ctor.getAnnotation(tag.class); }
321 public nonterminal getNonTerminal() { return (nonterminal)_ctor.getAnnotation(nonterminal.class); }
322 public String toString() { return _ctor.getName(); }
323 public int[] buildSequence(Production p) {
324 Annotation[][] annotations = _ctor.getParameterAnnotations();
325 int len = annotations.length;
327 String name = _ctor.getDeclaringClass().getName();
329 if (name.indexOf('$') > name.lastIndexOf('.')) {
334 String[] names = new String[len];
335 arg[] argtags = new arg[len];
336 for(int i=0; i<names.length; i++)
337 for(Annotation a : annotations[i+ofs])
338 if (a instanceof arg)
339 argtags[i+ofs] = (arg)a;
340 return buildSequence(p, names, argtags);
342 public Object plant(Object[] fields) {
344 Class[] argTypes = _ctor.getParameterTypes();
345 Object[] args = new Object[argTypes.length];
347 for(int i=0; i<args.length; i++) {
348 Object tgt = Reflection.lub(fields[i]);
349 if (argTypes[i] == String.class) tgt = stringify(tgt);
351 tgt = coerce(tgt, argTypes[i]);
352 System.err.println("setting a " + argTypes[i].getName() + " to " + Reflection.show(tgt));
355 return _ctor.newInstance(args);
356 } catch (Exception e) {
357 throw new RuntimeException(e);
361 public static class TargetMethod extends Target {
362 public final Method _method;
363 public TargetMethod(Method _method) { this._method = _method; }
364 public String getName() { return _method.getName(); }
365 public String toString() { return _method.getName(); }
366 public tag getTag() { return (tag)_method.getAnnotation(tag.class); }
367 public nonterminal getNonTerminal() { return (nonterminal)_method.getAnnotation(nonterminal.class); }
368 public int[] buildSequence(Production p) {
369 Annotation[][] annotations = _method.getParameterAnnotations();
370 String[] names = new String[annotations.length];
371 arg[] argtags = new arg[annotations.length];
372 for(int i=0; i<names.length; i++)
373 for(Annotation a : annotations[i])
374 if (a instanceof arg)
376 int[] ret = buildSequence(p, names, argtags);
379 public boolean isRaw() { return _method.isAnnotationPresent(raw.class); }
380 public Object invokeRaw(Iterable<Tree<Object>> t) {
382 return _method.invoke(null, new Object[] { t });
383 } catch (Exception e) {
384 throw new RuntimeException(e);
387 public Object plant(Object[] fields) {
389 Class[] argTypes = _method.getParameterTypes();
390 Object[] args = new Object[argTypes.length];
392 for(int i=0; i<args.length; i++) {
393 Object tgt = Reflection.lub(fields[i]);
394 if (argTypes[i] == String.class) tgt = stringify(tgt);
396 tgt = coerce(tgt, argTypes[i]);
397 System.err.println("setting a " + argTypes[i].getName() + " to " + Reflection.show(tgt));
400 System.err.println("invoking " + _method + " with " + Reflection.show(args));
401 return _method.invoke(null, args);
402 } catch (Exception e) {
403 throw new RuntimeException(e);
408 public static Object coerce(Object o, Class c) {
409 if (o==null) return null;
410 if (c.isInstance(o)) return o;
411 if (c == char.class) {
412 return o.toString().charAt(0);
415 if (o.getClass().isArray() &&
416 o.getClass().getComponentType().isArray() &&
417 o.getClass().getComponentType().getComponentType() == String.class &&
419 c.getComponentType() == String.class) {
420 String[] ret = new String[((Object[])o).length];
421 for(int i=0; i<ret.length; i++) {
422 StringBuffer sb = new StringBuffer();
423 for(Object ob : (Object[])(((Object[])o)[i]))
425 ret[i] = sb.toString();
430 if (c.isArray() && (c.getComponentType().isInstance(o))) {
431 Object[] ret = (Object[])Array.newInstance(c.getComponentType(), 1);
436 if (o.getClass().isArray() && c.isArray()) {
438 for(int i=0; i<((Object[])o).length; i++) {
439 Object ob = (((Object[])o)[i]);
441 System.err.println("no hit with " + c.getComponentType().getName() + " on " + Reflection.show(((Object[])o)[i]));
446 System.err.println("hit with " + c.getComponentType().getName());
447 return Array.newInstance(c.getComponentType(), ((Object[])o).length);
453 public static Union cached = null;
454 public static Union make() {
455 if (cached != null) return cached;
457 ReflectiveMeta m = new ReflectiveMeta();
458 Tree<String> res = new CharParser(MetaGrammar.make()).parse(new FileInputStream("tests/meta.g")).expand1();
459 MetaGrammar.Meta.MetaGrammarFile mgf = m.new MetaGrammarFile(res);
460 MetaGrammar.BuildContext bc = new MetaGrammar.BuildContext(mgf);
461 Union meta = mgf.get("s").build(bc);
462 Tree t = new CharParser(meta).parse(new FileInputStream("tests/meta.g")).expand1();
463 return cached = make(t, "s");
464 } catch (Exception e) {
465 throw new RuntimeException(e);
468 public static Union make(Tree t, String s) { return make(t, s, new ReflectiveMeta()); }
469 public static Union make(Tree t, String s, ReflectiveMeta rm) {
470 Tree.TreeFunctor<Object,Object> red = (Tree.TreeFunctor<Object,Object>)t.head();
471 MG.Grammar g = (MG.Grammar)red.invoke(t.children());
472 Context cx = new Context(g,rm);
474 for(MG.NonTerminal nt : g.nonterminals) {
475 System.out.println(nt.name);
476 Union el = (Union)cx.get(nt.name);
477 StringBuffer st = new StringBuffer();
479 System.err.println(st);
480 if (nt.name.equals(s)) u = el;
485 public static class MG {
486 public static @tag("grammar") class Grammar {
487 public NonTerminal get(String s) {
488 for(NonTerminal nt : nonterminals)
489 if (nt.name.equals(s))
493 public @arg("NonTerminal") NonTerminal[] nonterminals;
494 public String toString() {
496 for(NonTerminal nt : nonterminals) ret += nt + ", ";
500 public abstract static class Un extends El {
501 public Seq[][] sequences;
502 public void build(Context cx, Union u) {
503 HashSet<Sequence> bad2 = new HashSet<Sequence>();
504 for(int i=0; i<sequences.length; i++) {
505 Seq[] group = sequences[i];
506 Union u2 = new Union();
507 if (sequences.length==1) u2 = u;
508 for(int j=0; j<group.length; j++) {
509 group[j].build(cx, u2, false);
511 if (sequences.length==1) break;
512 Sequence seq = Sequence.singleton(u2);
513 for(Sequence s : bad2) {
518 bad2.add(Sequence.singleton(u2));
522 public static class NonTerminal extends Un {
523 public String name = null;
524 public @nonterminal("NonTerminal") NonTerminal(@arg("Word") String name,
525 @arg("RHS") Seq[][] sequences) {
527 this.sequences = sequences;
529 public Element build(Context cx) { return cx.get(name); }
532 public static class AnonUn extends Un {
533 public @tag("(") AnonUn(Seq[][] sequences) {
534 this.sequences = sequences;
536 public Element build(Context cx) {
537 Union ret = new Union();
543 //public static @tag void range(char c) { }
544 public static class Range {
545 public @tag("range") Range(char only) { first = only; last = only; }
546 public @tag("-") Range(char first, char last) { this.first = first; this.last = last; }
550 public static abstract class El {
551 public String getLabel() { return null; }
552 public String getOwnerTag() { return null; }
553 public boolean drop() { return false; }
554 public abstract Element build(Context cx);
556 public static class Drop extends El {
558 public Drop(El e) { this.e = e; }
559 public String getLabel() { return null; }
560 public boolean drop() { return true; }
561 public String getOwnerTag() { return e.getOwnerTag(); }
562 public Element build(Context cx) { return e.build(cx); }
564 public static class Label extends El {
567 public Label(String label, El e) { this.e = e; this.label = label; }
568 public String getLabel() { return label; }
569 public String getOwnerTag() { return e.getOwnerTag(); }
570 public Element build(Context cx) { return e.build(cx); }
572 public static /*abstract*/ class Seq {
573 HashSet<Seq> and = new HashSet<Seq>();
574 HashSet<Seq> not = new HashSet<Seq>();
579 public Seq(El e) { this(new El[] { e }); }
580 public Seq(El[] elements) { this.elements = elements; }
581 public Seq tag(String tag) { this.tag = tag; return this; }
582 public Seq follow(El follow) { this.follow = follow; return this; }
584 Seq ret = new Seq(elements);
591 public Seq and(Seq s) { and.add(s); s.lame = true; return this; }
592 public Seq andnot(Seq s) { not.add(s); s.lame = true; return this; }
593 public Seq separate(El sep) {
594 El[] elements = new El[this.elements.length * 2 - 1];
595 for(int i=0; i<this.elements.length; i++) {
596 elements[i*2] = this.elements[i];
597 if (i<this.elements.length-1)
598 elements[i*2+1] = new Drop(sep);
600 this.elements = elements;
603 public Sequence build(Context cx, Union u, boolean lame) {
604 Sequence ret = build0(cx, lame || this.lame);
605 for(Seq s : and) { Sequence dork = s.build(cx, u, true); ret = ret.and(dork); }
606 for(Seq s : not) { Sequence dork = s.build(cx, u, true); ret = ret.not(dork); }
611 public Sequence build0(Context cx, boolean lame) {
612 boolean unwrap = false;
613 boolean dropAll = lame;
614 if (tag!=null && tag.equals("[]")) unwrap = true;
615 if (tag!=null && "()".equals(tag)) dropAll = true;
616 Object[] labels = new Object[elements.length];
617 boolean[] drops = new boolean[elements.length];
618 Element[] els = new Element[elements.length];
619 for(int i=0; i<elements.length; i++) {
620 labels[i] = elements[i].getLabel();
621 drops[i] = elements[i].drop();
622 els[i] = elements[i].build(cx);
623 if (elements[i].getOwnerTag() != null)
624 tag = elements[i].getOwnerTag();
627 if (dropAll) ret = Sequence.drop(els, false);
628 else if (unwrap) ret = Sequence.unwrap(els, cx.rm.repeatTag(), drops);
629 else if (tag!=null) {
630 ret = cx.rm.resolveTag(tag, cx.cnt, els, labels, drops);
633 for(int i=0; i<els.length; i++)
635 if (idx==-1) idx = i;
636 else throw new Error("multiple non-dropped elements in sequence: " + Sequence.drop(els,false));
637 if (idx != -1) ret = Sequence.singleton(els, idx);
638 else ret = Sequence.drop(els, false);
640 if (this.follow != null)
641 ret.follow = MetaGrammar.infer(this.follow.build(cx));
642 ret.lame = this.lame;
646 public static @tag("&") Seq and(Seq s, El[] elements) { return s.and(seq(elements)); }
647 public static @tag("&~") Seq andnot(Seq s, El[] elements) { return s.andnot(seq(elements)); }
648 public static @tag("->") Seq arrow(Seq s, El e) { return s.follow(e); }
649 public static @tag("::") Seq tag(String tagname, Seq s) { return s.tag(tagname); }
650 public static @tag("/") Seq slash(Seq s, El e) { return s.separate(e); }
652 public static @tag("ps") Seq seq(El[] elements) { return new Seq(elements); }
653 public static @tag Seq psx(Seq s) { return s; }
654 public static @tag(":") El colon(String s, El e) { return new Label(s, e); }
655 public static @tag(")") void close(String foo) { throw new Error("not supported"); }
656 public static @tag("()") El epsilon() { return new Constant(Union.epsilon); }
658 public static @tag("nonTerminal") class NonTerminalReference extends El {
659 public @arg String nonTerminal;
660 public Element build(Context cx) {
661 return cx.get(nonTerminal);
665 public static class StringLiteral extends Constant {
666 public @tag("literal") StringLiteral(String string) { super(CharRange.string(string)); }
667 public boolean drop() { return true; }
670 public static class CharClass extends El {
672 public @tag("[") CharClass(Range[] ranges) { this.ranges = ranges; }
673 public Element build(Context cx) {
674 edu.berkeley.sbp.util.Range.Set set = new edu.berkeley.sbp.util.Range.Set();
675 for(Range r : ranges)
676 set.add(r.first, r.last);
677 return CharRange.set(set);
681 public static @tag("{") class XTree extends El {
682 public @arg Seq body;
683 public Element build(Context cx) {
688 public static class Rep extends El {
690 public boolean zero, many, max;
691 public Rep(El e, El sep, boolean zero, boolean many, boolean max) {
692 this.e = e; this.sep = sep; this.zero = zero; this.many = many; this.max = max;}
693 public Element build(Context cx) {
695 ? Sequence.repeat(e.build(cx), zero, many, sep==null ? null : sep.build(cx), cx.rm.repeatTag())
697 ? Sequence.repeatMaximal(MetaGrammar.infer(e.build(cx)), zero, many, cx.rm.repeatTag())
698 : Sequence.repeatMaximal(e.build(cx), zero, many, MetaGrammar.infer(sep.build(cx)), cx.rm.repeatTag());
701 public static class Constant extends El {
703 public Constant(Element constant) { this.constant = constant; }
704 public Element build(Context cx) { return constant; }
706 public abstract static class PostProcess extends El {
708 public PostProcess(El e) { this.e = e; }
709 public Element build(Context cx) { return postProcess(e.build(cx)); }
710 public abstract Element postProcess(Element e);
713 // FIXME: it would be nice if we could hoist this into "Rep"
714 public static @tag("++") El plusmax(final El e) { return new Rep(e, null, false, true, true); }
715 public static @tag("+") El plus(final El e) { return new Rep(e, null, false, true, false); }
716 public static @tag("++/") El plusmaxfollow(final El e, final El sep) { return new Rep(e, sep, false, true, true); }
717 public static @tag("+/") El plusfollow(final El e, final El sep) { return new Rep(e, sep, false, true, false); }
718 public static @tag("**") El starmax(final El e) { return new Rep(e, null, true, true, true); }
719 public static @tag("*") El star(final El e) { return new Rep(e, null, true, true, false); }
720 public static @tag("**/") El starmaxfollow(final El e, final El sep) { return new Rep(e, sep, true, true, true); }
721 public static @tag("*/") El starfollow(final El e, final El sep) { return new Rep(e, sep, true, true, false); }
722 public static @tag("?") El question(final El e) { return new Rep(e, null, true, true, false); }
724 public static @tag("!") El bang(final El e) { return new Drop(e); }
726 public static @tag("^") El caret(final String s) {
727 return new Drop(new Constant(CharRange.string(s)) {
728 public String getOwnerTag() { return s; }
732 public static @tag("~") El tilde(final El e) {
733 return new PostProcess(e) {
734 public Element postProcess(Element e) {
735 return MetaGrammar.infer((Topology<Character>)Atom.toAtom(e).complement());
738 public static @tag("^^") void doublecaret(final El e) { throw new Error("not implemented"); }
740 //public static @tag("(") El subexpression(Seq[][] rhs) { return new NonTerminal(rhs); }
742 public static @nonterminal("Word") String word(String s) { return s; }
743 public static @nonterminal("Quoted") String quoted(String s) { return s; }
744 public static @nonterminal("escaped") String c(char c) { return c+""; }
745 public static @tag("\"\"") String emptystring() { return ""; }
746 public static @tag("\n") String retur() { return "\n"; }
747 public static @tag("\r") String lf() { return "\r"; }
750 public static class Context {
751 HashMap<String,Union> map = new HashMap<String,Union>();
752 private MG.Grammar grammar;
753 public String cnt = null;
754 private ReflectiveMeta rm;
755 public Context(MG.Grammar g, ReflectiveMeta rm) {
759 public Union build() {
761 for(MG.NonTerminal nt : grammar.nonterminals) {
762 Union u = get(nt.name);
763 if ("s".equals(nt.name))
768 public Context(Tree t, ReflectiveMeta rm) {
770 Tree.TreeFunctor<Object,Object> red = (Tree.TreeFunctor<Object,Object>)t.head();
771 this.grammar = (MG.Grammar)red.invoke(t.children());
773 public Union peek(String name) { return map.get(name); }
774 public void put(String name, Union u) { map.put(name, u); }
775 public Union get(String name) {
776 Union ret = map.get(name);
777 if (ret != null) return ret;
778 ret = new Union(name);
780 MG.NonTerminal nt = grammar.get(name);
782 System.err.println("*** warning could not find " + name);