import edu.berkeley.sbp.*;
import edu.berkeley.sbp.chr.*;
import java.util.*;
+import java.lang.annotation.*;
+import java.lang.reflect.*;
import java.io.*;
public class Demo {
+
+ public static boolean harsh = false;
+
public static void main(String[] s) throws Exception {
- Tree<String> gram = new CharParser(MetaGrammar.make()).parse(new FileInputStream(s[0])).expand1();
- MetaGrammar g = (MetaGrammar)new MetaGrammar().walk(gram);
- Union meta = g.done();
- //Tree<String> out = new CharParser(meta).parse(new FileInputStream(s[1])).expand1();
- Forest<String> out = new CharParser(meta).parse(new FileInputStream(s[1]));
- GraphViz gv = new GraphViz();
- out.toGraphViz(gv);
- gv.dump(new PrintWriter(new OutputStreamWriter(System.out)));
+
+ ReflectiveMeta m = new ReflectiveMeta();
+ Tree<String> res = new CharParser(MetaGrammar.make()).parse(new FileInputStream(s[0])).expand1();
+ MetaGrammar.Meta.MetaGrammarFile mgf = m.new MetaGrammarFile(res);
+ MetaGrammar.BuildContext bc = new MetaGrammar.BuildContext(mgf);
+
+ Union meta = mgf.get("s").build(bc);
+ Tree t = new CharParser(meta).parse(new FileInputStream(s[1])).expand1();
+
+ Union u = Demo.make(t, "s");
+
+ System.err.println();
+ System.err.println("== parsing with parsed grammar =================================================================================");
+ t = new CharParser((Union)u).parse(new FileInputStream(s[1])).expand1();
+ System.out.println(t.toPrettyString());
+
+ System.err.println("== parsing with parsed-parsed grammar ==========================================================================");
+ t = new CharParser(new Context(t, m).build()).parse(new FileInputStream(s[1])).expand1();
+ System.out.println(t.toPrettyString());
+ }
+
+ public static class ReflectiveMetaPlain extends ReflectiveMeta {
+ public Object repeatTag() { return null; }
+ public Sequence tryResolveTag(String tag, String nonTerminalName, Element[] els, Object[] labels, boolean[] drops) {
+ return null; }
+ public Sequence resolveTag(String tag, String nonTerminalName, Element[] els, Object[] labels, boolean[] drops) {
+ return Sequence.rewritingSequence(tag, els, labels, drops);
+ }
+ }
+
+ public static class ReflectiveMeta extends MetaGrammar.Meta {
+ private final Class _cl;
+ private final Class[] _inner;
+ public ReflectiveMeta() {
+ this(MG.class,
+ new Class[] {
+ MG.Grammar.class,
+ MG.AnonUn.class,
+ MG.Range.class,
+ MG.El.class,
+ MG.Seq.class,
+ MG.NonTerminal.class,
+ MG.NonTerminalReference.class,
+ MG.StringLiteral.class,
+ MG.XTree.class,
+ MG.CharClass.class
+ });
+ }
+ public ReflectiveMeta(Class c, Class[] inner) {
+ this._cl = c;
+ this._inner = inner;
+ }
+ private boolean match(Method m, String s) { return match(m.getAnnotation(tag.class), null, s); }
+ private boolean match(tag t, Class c, String s) {
+ if (t==null) return false;
+ if (t.value().equals(s)) return true;
+ if (c != null && t.equals("") && c.getSimpleName().equals(s)) return true;
+ return false;
+ }
+ /*
+ private boolean match(nonterminal t, Class c, String s) {
+ if (t==null) return false;
+ if (t.value().equals(s)) return true;
+ if (c != null && t.equals("") && c.getSimpleName().equals(s)) return true;
+ return false;
+ }
+ */
+ private boolean match(Class c, String s, String nonTerminalName) {
+ if (match((tag)c.getAnnotation(tag.class), c, s)) return true;
+ //if (match((nonterminal)c.getAnnotation(tag.class), c, nonTerminalName)) return true;
+ return false;
+ }
+ public boolean match(Constructor con, String s, String nonTerminalName) {
+ Class c = con.getDeclaringClass();
+ if (match((tag)con.getAnnotation(tag.class), null, s)) return true;
+ //if (match((nonterminal)con.getAnnotation(tag.class), c, s)) return true;
+ return false;
+ }
+ public Object repeatTag() {
+ return new Tree.ArrayBuildingTreeFunctor<Object>();
+ }
+ public Sequence tryResolveTag(String tag, String nonTerminalName, Element[] els, Object[] labels, boolean[] drops) {
+ Production p = new Production(tag, nonTerminalName, els, labels, drops);
+ for(Method m : _cl.getMethods())
+ if (new TargetMethod(m).isCompatible(p))
+ return new TargetMethod(m).makeSequence(p);
+ for(Class c : _inner)
+ for(Constructor con : c.getConstructors())
+ if (new TargetConstructor(con).isCompatible(p))
+ return new TargetConstructor(con).makeSequence(p);
+ for(Class c : _inner)
+ if (new TargetClass(c).isCompatible(p))
+ return new TargetClass(c).makeSequence(p);
+ return null;
+ }
+ public Sequence resolveTag(String tag, String nonTerminalName, Element[] els, Object[] labels, boolean[] drops) {
+ Sequence ret = tryResolveTag(tag, nonTerminalName, els, labels, drops);
+ if (ret != null) return ret;
+ String message = "could not find a Java method/class/ctor matching tag \""+tag+
+ "\", nonterminal \""+nonTerminalName+"\" with " + els.length + " arguments";
+ if (harsh) {
+ throw new RuntimeException(message);
+ } else {
+ System.err.println(message);
+ return Sequence.rewritingSequence(tag, els, labels, drops);
+ }
+ }
+ }
+
+
+ /**
+ * Constructors, classes, and methods with this attribute will
+ * match every production of the nonterminal called "value()"
+ * that is arg-compatible. If value() is undefined, then the
+ * class/constructor/method name is used.
+ */
+ /*
+ @Retention(RetentionPolicy.RUNTIME) public static @interface nonterminal { String value() default ""; }
+ */
+
+ @Retention(RetentionPolicy.RUNTIME) public static @interface raw { }
+
+ /**
+ * Constructors, classes, and methods with this attribute will
+ * match every tree tagged with "value()" that is arg-compatible.
+ * If value() is undefined, then the class/constructor/method
+ * name is used.
+ */
+ @Retention(RetentionPolicy.RUNTIME) public static @interface tag { String value() default ""; }
+
+ /**
+ * If any parameter to a method or field in a class has a named
+ * arg-tag, that parameter/field matches the child of the tree
+ * which either has that label or else is a reference to a
+ * nonterminal with the corresponding name.
+ *
+ * The remaining non-named arg-tags match the remaining children
+ * of the tree in sequential order.
+ *
+ * If any arg-tagged parameters/fields remain, the match fails.
+ * If there were no arg-tagged parameters-fields, it is as if all
+ * of them were non-named and arg-tagged.
+ *
+ * A method/constructor is arg-compatible if all of its arguments
+ * are arg-compatible.
+ *
+ * A class is arg-compatible if all of its fields are
+ * arg-compatible, or if one of its constructors is arg-compatible.
+ *
+ */
+ @Retention(RetentionPolicy.RUNTIME) public static @interface arg { String value() default ""; }
+
+ public static class Production {
+ public String tag;
+ public String nonTerminal;
+ public Object[] labels;
+ public boolean[] drops;
+ public Element[] elements;
+ public int count = 0;
+ public Production(String tag, String nonTerminal, Element[] elements, Object[] labels, boolean[] drops) {
+ this.tag = tag;
+ this.elements = elements;
+ this.nonTerminal = nonTerminal;
+ this.labels = labels;
+ this.drops = drops;
+ for(int i=0; i<drops.length; i++)
+ if (!drops[i])
+ count++;
+ }
+ }
+
+ public static abstract class Target {
+ public abstract int[] buildSequence(Production p);
+ private Reflection.Bindable _bindable;
+ public Target(Reflection.Bindable b) { this._bindable = b; }
+
+ public String getName() { return _bindable.getSimpleName(); }
+ public tag getTag() { return (tag)_bindable.getAnnotation(tag.class); }
+ //public nonterminal getNonTerminal() { return (nonterminal)_bindable.getAnnotation(tag.class); }
+ public String toString() { return _bindable.getSimpleName(); }
+ public Object plant(Object[] fields) { return _bindable.impose(fields); }
+ public boolean isRaw() { return _bindable.isAnnotationPresent(raw.class); }
+ public Object invokeRaw(Iterable<Tree<Object>> t) { return _bindable.impose(new Object[] { t }); }
+
+ public boolean isCompatible(Production p) {
+ tag t = getTag();
+ if (t != null &&
+ (t.value().equals(p.tag) ||
+ (t.value().equals("") && getName().equals(p.tag))))
+ return buildSequence(p)!=null;
+
+ tag n = getTag();
+ if (n != null &&
+ (n.value().equals(p.nonTerminal) ||
+ (n.value().equals("") && getName().equals(p.nonTerminal))))
+ return buildSequence(p)!=null;
+
+ return false;
+ }
+
+ public int[] buildSequence(Production p, String[] names, arg[] argtags) {
+ int argTagged = 0;
+ for(int i=0; i<argtags.length; i++)
+ if (argtags[i] != null)
+ argTagged++;
+
+ // FIXME: can be smarter here
+ if (names.length==p.count) {
+ int[] ret = new int[p.count];
+ for(int i=0; i<p.count; i++) ret[i] = i;
+ return ret;
+ } else if (argTagged==p.count) {
+ int[] ret = new int[argtags.length];
+ int j = 0;
+ for(int i=0; i<argtags.length; i++)
+ ret[i] = argtags[i]==null ? -1 : (j++);
+ return ret;
+ } else {
+ return null;
+ }
+ }
+ public Sequence makeSequence(Production p) {
+ return Sequence.rewritingSequence(new TargetReducer(p, buildSequence(p), "reducer-"+this),
+ p.elements, p.labels, p.drops);
+ }
+
+ public class TargetReducer implements Tree.TreeFunctor<Object,Object> {
+ private Production p;
+ private int[] map;
+ private String name;
+ public TargetReducer(Production p, int[] map, String name) {
+ this.p = p;
+ this.map = map;
+ this.name = name;
+ }
+ public String toString() { return name; }
+ public Object invoke(Iterable<Tree<Object>> t) {
+ if (isRaw()) return invokeRaw(t);
+ ArrayList ret = new ArrayList();
+ for(Tree tc : t) {
+ if (tc.head() != null && tc.head() instanceof Functor)
+ ret.add(((Tree.TreeFunctor<Object,Object>)tc.head()).invoke(tc.children()));
+ else if (tc.numChildren() == 0)
+ ret.add(tc.head());
+ else {
+ System.err.println("FIXME: don't know what to do about " + tc);
+ ret.add(null);
+ }
+ }
+ System.err.println("input tree: " + t);
+ Object[] o = (Object[])ret.toArray(new Object[0]);
+ int max = 0;
+ for(int i=0; i<map.length; i++) max = Math.max(map[i], max);
+ Object[] o2 = new Object[max+1];
+ for(int i=0; i<o.length; i++) o2[map[i]] = o[i];
+ return plant(o2);
+ }
+ }
+ }
+
+ public static class TargetClass extends Target {
+ public final Class _class;
+ public TargetClass(Class _class) { super(Reflection.Bindable.create(_class)); this._class = _class; }
+ public int[] buildSequence(Production p) {
+ Field[] f = _class.getDeclaredFields();
+ String[] names = new String[f.length];
+ arg[] argtags = new arg[f.length];
+ for(int i=0; i<f.length; i++) {
+ names[i] = f[i].getName();
+ argtags[i] = f[i].getAnnotation(arg.class);
+ }
+ int[] ret = buildSequence(p, names, argtags);
+ if (ret!=null) return ret;
+ for(Constructor c : _class.getConstructors())
+ if (new TargetConstructor(c).buildSequence(p)!=null)
+ return new TargetConstructor(c).buildSequence(p);
+ return null;
+ }
+ }
+
+ public static class TargetConstructor extends Target {
+ public final Constructor _ctor;
+ public TargetConstructor(Constructor _ctor) { super(Reflection.Bindable.create(_ctor)); this._ctor = _ctor; }
+ public int[] buildSequence(Production p) {
+ Annotation[][] annotations = _ctor.getParameterAnnotations();
+ int len = annotations.length;
+ int ofs = 0;
+ String name = _ctor.getDeclaringClass().getName();
+ /*
+ if (name.indexOf('$') > name.lastIndexOf('.')) {
+ len--;
+ ofs++;
+ }
+ */
+ String[] names = new String[len];
+ arg[] argtags = new arg[len];
+ for(int i=0; i<names.length; i++)
+ for(Annotation a : annotations[i+ofs])
+ if (a instanceof arg)
+ argtags[i+ofs] = (arg)a;
+ return buildSequence(p, names, argtags);
+ }
+ }
+ public static class TargetMethod extends Target {
+ public final Method _method;
+ public TargetMethod(Method _method) { super(Reflection.Bindable.create(_method)); this._method = _method; }
+ public int[] buildSequence(Production p) {
+ Annotation[][] annotations = _method.getParameterAnnotations();
+ String[] names = new String[annotations.length];
+ arg[] argtags = new arg[annotations.length];
+ for(int i=0; i<names.length; i++)
+ for(Annotation a : annotations[i])
+ if (a instanceof arg)
+ argtags[i] = (arg)a;
+ int[] ret = buildSequence(p, names, argtags);
+ return ret;
+ }
+ }
+
+ public static Union cached = null;
+ public static Union make() {
+ if (cached != null) return cached;
+ try {
+ ReflectiveMeta m = new ReflectiveMeta();
+ Tree<String> res = new CharParser(MetaGrammar.make()).parse(new FileInputStream("tests/meta.g")).expand1();
+ MetaGrammar.Meta.MetaGrammarFile mgf = m.new MetaGrammarFile(res);
+ MetaGrammar.BuildContext bc = new MetaGrammar.BuildContext(mgf);
+ Union meta = mgf.get("s").build(bc);
+ Tree t = new CharParser(meta).parse(new FileInputStream("tests/meta.g")).expand1();
+ return cached = make(t, "s");
+ } catch (Exception e) {
+ throw new RuntimeException(e);
+ }
+ }
+ public static Union make(Tree t, String s) { return make(t, s, new ReflectiveMeta()); }
+ public static Union make(Tree t, String s, ReflectiveMeta rm) {
+ Tree.TreeFunctor<Object,Object> red = (Tree.TreeFunctor<Object,Object>)t.head();
+ MG.Grammar g = (MG.Grammar)red.invoke(t.children());
+ Context cx = new Context(g,rm);
+ Union u = null;
+ for(MG.NonTerminal nt : g.nonterminals) {
+ System.out.println(nt.name);
+ Union el = (Union)cx.get(nt.name);
+ StringBuffer st = new StringBuffer();
+ el.toString(st);
+ System.err.println(st);
+ if (nt.name.equals(s)) u = el;
+ }
+ return u;
+ }
+
+ public static class MG {
+ public static @tag("grammar") class Grammar {
+ public NonTerminal get(String s) {
+ for(NonTerminal nt : nonterminals)
+ if (nt.name.equals(s))
+ return nt;
+ return null;
+ }
+ public @arg("NonTerminal") NonTerminal[] nonterminals;
+ public String toString() {
+ String ret = "[ ";
+ for(NonTerminal nt : nonterminals) ret += nt + ", ";
+ return ret + " ]";
+ }
+ }
+ public abstract static class Un extends El {
+ public Seq[][] sequences;
+ public void build(Context cx, Union u) {
+ HashSet<Sequence> bad2 = new HashSet<Sequence>();
+ for(int i=0; i<sequences.length; i++) {
+ Seq[] group = sequences[i];
+ Union u2 = new Union();
+ if (sequences.length==1) u2 = u;
+ for(int j=0; j<group.length; j++) {
+ group[j].build(cx, u2, false);
+ }
+ if (sequences.length==1) break;
+ Sequence seq = Sequence.singleton(u2);
+ for(Sequence s : bad2) {
+ s.lame = true;
+ seq = seq.not(s);
+ }
+ u.add(seq);
+ bad2.add(Sequence.singleton(u2));
+ }
+ }
+ }
+ public static class NonTerminal extends Un {
+ public String name = null;
+ public @tag("=") NonTerminal(@arg("Word") String name,
+ @arg("RHS") Seq[][] sequences) {
+ this.name = name;
+ this.sequences = sequences;
+ }
+ public Element build(Context cx) { return cx.get(name); }
+ }
+
+ public static class AnonUn extends Un {
+ public @tag("(") AnonUn(Seq[][] sequences) {
+ this.sequences = sequences;
+ }
+ public Element build(Context cx) {
+ Union ret = new Union();
+ build(cx, ret);
+ return ret;
+ }
+ }
+
+ //public static @tag void range(char c) { }
+ public static class Range {
+ public @tag("range") Range(char only) { first = only; last = only; }
+ public @tag("-") Range(char first, char last) { this.first = first; this.last = last; }
+ public char first;
+ public char last;
+ }
+ public static abstract class El {
+ public String getLabel() { return null; }
+ public String getOwnerTag() { return null; }
+ public boolean drop() { return false; }
+ public abstract Element build(Context cx);
+ }
+ public static class Drop extends El {
+ public El e;
+ public Drop(El e) { this.e = e; }
+ public String getLabel() { return null; }
+ public boolean drop() { return true; }
+ public String getOwnerTag() { return e.getOwnerTag(); }
+ public Element build(Context cx) { return e.build(cx); }
+ }
+ public static class Label extends El {
+ public String label;
+ public El e;
+ public Label(String label, El e) { this.e = e; this.label = label; }
+ public String getLabel() { return label; }
+ public String getOwnerTag() { return e.getOwnerTag(); }
+ public Element build(Context cx) { return e.build(cx); }
+ }
+ public static /*abstract*/ class Seq {
+ HashSet<Seq> and = new HashSet<Seq>();
+ HashSet<Seq> not = new HashSet<Seq>();
+ El[] elements;
+ El follow;
+ String tag = null;
+ boolean lame;
+ public Seq(El e) { this(new El[] { e }); }
+ public Seq(El[] elements) { this.elements = elements; }
+ public Seq tag(String tag) { this.tag = tag; return this; }
+ public Seq follow(El follow) { this.follow = follow; return this; }
+ public Seq dup() {
+ Seq ret = new Seq(elements);
+ ret.and.addAll(and);
+ ret.not.addAll(not);
+ ret.follow = follow;
+ ret.tag = tag;
+ return ret;
+ }
+ public Seq and(Seq s) { and.add(s); s.lame = true; return this; }
+ public Seq andnot(Seq s) { not.add(s); s.lame = true; return this; }
+ public Seq separate(El sep) {
+ El[] elements = new El[this.elements.length * 2 - 1];
+ for(int i=0; i<this.elements.length; i++) {
+ elements[i*2] = this.elements[i];
+ if (i<this.elements.length-1)
+ elements[i*2+1] = new Drop(sep);
+ }
+ this.elements = elements;
+ return this;
+ }
+ public Sequence build(Context cx, Union u, boolean lame) {
+ Sequence ret = build0(cx, lame || this.lame);
+ for(Seq s : and) { Sequence dork = s.build(cx, u, true); ret = ret.and(dork); }
+ for(Seq s : not) { Sequence dork = s.build(cx, u, true); ret = ret.not(dork); }
+ u.add(ret);
+ ret.lame = lame;
+ return ret;
+ }
+ public Sequence build0(Context cx, boolean lame) {
+ boolean unwrap = false;
+ boolean dropAll = lame;
+ if (tag!=null && tag.equals("[]")) unwrap = true;
+ if (tag!=null && "()".equals(tag)) dropAll = true;
+ Object[] labels = new Object[elements.length];
+ boolean[] drops = new boolean[elements.length];
+ Element[] els = new Element[elements.length];
+ for(int i=0; i<elements.length; i++) {
+ labels[i] = elements[i].getLabel();
+ drops[i] = elements[i].drop();
+ els[i] = elements[i].build(cx);
+ if (elements[i].getOwnerTag() != null)
+ tag = elements[i].getOwnerTag();
+ }
+ Sequence ret = null;
+ if (dropAll) ret = Sequence.drop(els, false);
+ else if (unwrap) ret = Sequence.unwrap(els, cx.rm.repeatTag(), drops);
+ else if (tag!=null) {
+ ret = cx.rm.resolveTag(tag, cx.cnt, els, labels, drops);
+ } else {
+ int idx = -1;
+ for(int i=0; i<els.length; i++)
+ if (!drops[i])
+ if (idx==-1) idx = i;
+ else throw new Error("multiple non-dropped elements in sequence: " + Sequence.drop(els,false));
+ if (idx != -1) ret = Sequence.singleton(els, idx);
+ else ret = Sequence.drop(els, false);
+ }
+ if (this.follow != null)
+ ret.follow = MetaGrammar.infer(this.follow.build(cx));
+ ret.lame = this.lame;
+ return ret;
+ }
+ }
+ public static @tag("&") Seq and(Seq s, El[] elements) { return s.and(seq(elements)); }
+ public static @tag("&~") Seq andnot(Seq s, El[] elements) { return s.andnot(seq(elements)); }
+ public static @tag("->") Seq arrow(Seq s, El e) { return s.follow(e); }
+ public static @tag("::") Seq tag(String tagname, Seq s) { return s.tag(tagname); }
+ public static @tag("/") Seq slash(Seq s, El e) { return s.separate(e); }
+
+ public static @tag("ps") Seq seq(El[] elements) { return new Seq(elements); }
+ public static @tag Seq psx(Seq s) { return s; }
+ public static @tag(":") El colon(String s, El e) { return new Label(s, e); }
+ public static @tag(")") void close(String foo) { throw new Error("not supported"); }
+ public static @tag("()") El epsilon() { return new Constant(Union.epsilon); }
+
+ public static @tag("nonTerminal") class NonTerminalReference extends El {
+ public @arg String nonTerminal;
+ public Element build(Context cx) {
+ return cx.get(nonTerminal);
+ }
+ }
+
+ public static class StringLiteral extends Constant {
+ public @tag("literal") StringLiteral(String string) { super(CharRange.string(string)); }
+ public boolean drop() { return true; }
+ }
+
+ public static class CharClass extends El {
+ Range[] ranges;
+ public @tag("[") CharClass(Range[] ranges) { this.ranges = ranges; }
+ public Element build(Context cx) {
+ edu.berkeley.sbp.util.Range.Set set = new edu.berkeley.sbp.util.Range.Set();
+ for(Range r : ranges)
+ set.add(r.first, r.last);
+ return CharRange.set(set);
+ }
+ }
+
+ public static @tag("{") class XTree extends El {
+ public @arg Seq body;
+ public Element build(Context cx) {
+ throw new Error();
+ }
+ }
+
+ public static class Rep extends El {
+ public El e, sep;
+ public boolean zero, many, max;
+ public Rep(El e, El sep, boolean zero, boolean many, boolean max) {
+ this.e = e; this.sep = sep; this.zero = zero; this.many = many; this.max = max;}
+ public Element build(Context cx) {
+ return (!max)
+ ? Sequence.repeat(e.build(cx), zero, many, sep==null ? null : sep.build(cx), cx.rm.repeatTag())
+ : sep==null
+ ? Sequence.repeatMaximal(MetaGrammar.infer(e.build(cx)), zero, many, cx.rm.repeatTag())
+ : Sequence.repeatMaximal(e.build(cx), zero, many, MetaGrammar.infer(sep.build(cx)), cx.rm.repeatTag());
+ }
+ }
+ public static class Constant extends El {
+ Element constant;
+ public Constant(Element constant) { this.constant = constant; }
+ public Element build(Context cx) { return constant; }
+ }
+ public abstract static class PostProcess extends El {
+ El e;
+ public PostProcess(El e) { this.e = e; }
+ public Element build(Context cx) { return postProcess(e.build(cx)); }
+ public abstract Element postProcess(Element e);
+ }
+
+ // FIXME: it would be nice if we could hoist this into "Rep"
+ public static @tag("++") El plusmax(final El e) { return new Rep(e, null, false, true, true); }
+ public static @tag("+") El plus(final El e) { return new Rep(e, null, false, true, false); }
+ public static @tag("++/") El plusmaxfollow(final El e, final El sep) { return new Rep(e, sep, false, true, true); }
+ public static @tag("+/") El plusfollow(final El e, final El sep) { return new Rep(e, sep, false, true, false); }
+ public static @tag("**") El starmax(final El e) { return new Rep(e, null, true, true, true); }
+ public static @tag("*") El star(final El e) { return new Rep(e, null, true, true, false); }
+ public static @tag("**/") El starmaxfollow(final El e, final El sep) { return new Rep(e, sep, true, true, true); }
+ public static @tag("*/") El starfollow(final El e, final El sep) { return new Rep(e, sep, true, true, false); }
+ public static @tag("?") El question(final El e) { return new Rep(e, null, true, true, false); }
+
+ public static @tag("!") El bang(final El e) { return new Drop(e); }
+
+ public static @tag("^") El caret(final String s) {
+ return new Drop(new Constant(CharRange.string(s)) {
+ public String getOwnerTag() { return s; }
+ });
+ }
+
+ public static @tag("~") El tilde(final El e) {
+ return new PostProcess(e) {
+ public Element postProcess(Element e) {
+ return MetaGrammar.infer((Topology<Character>)Atom.toAtom(e).complement());
+ } }; }
+
+ public static @tag("^^") void doublecaret(final El e) { throw new Error("not implemented"); }
+
+ //public static @tag("(") El subexpression(Seq[][] rhs) { return new NonTerminal(rhs); }
+
+ public static @tag("Word") String word(String s) { return s; }
+ public static @tag("Quoted") String quoted(String s) { return s; }
+ public static @tag("escaped") String c(char c) { return c+""; }
+ public static @tag("\"\"") String emptystring() { return ""; }
+ public static @tag("\n") String retur() { return "\n"; }
+ public static @tag("\r") String lf() { return "\r"; }
+
+ }
+ public static class Context {
+ HashMap<String,Union> map = new HashMap<String,Union>();
+ private MG.Grammar grammar;
+ public String cnt = null;
+ private ReflectiveMeta rm;
+ public Context(MG.Grammar g, ReflectiveMeta rm) {
+ this.grammar = g;
+ this.rm = rm;
+ }
+ public Union build() {
+ Union ret = null;
+ for(MG.NonTerminal nt : grammar.nonterminals) {
+ Union u = get(nt.name);
+ if ("s".equals(nt.name))
+ ret = u;
+ }
+ return ret;
+ }
+ public Context(Tree t, ReflectiveMeta rm) {
+ this.rm = rm;
+ Tree.TreeFunctor<Object,Object> red = (Tree.TreeFunctor<Object,Object>)t.head();
+ this.grammar = (MG.Grammar)red.invoke(t.children());
+ }
+ public Union peek(String name) { return map.get(name); }
+ public void put(String name, Union u) { map.put(name, u); }
+ public Union get(String name) {
+ Union ret = map.get(name);
+ if (ret != null) return ret;
+ ret = new Union(name);
+ map.put(name, ret);
+ MG.NonTerminal nt = grammar.get(name);
+ if (nt==null) {
+ System.err.println("*** warning could not find " + name);
+ } else {
+ String old = cnt;
+ cnt = name;
+ nt.build(this, ret);
+ cnt = old;
+ }
+ return ret;
+ }
+
}
}
projects / sbp.git / blobdiff