X-Git-Url: http://git.megacz.com/?p=sbp.git;a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2Fmeta%2FGrammarAST.java;h=0b4ba07d9d21cc74210d2cc4ffd863bf9d7069a5;hp=297886b36f69cfe5427d71d5020aacf9a04b2dc5;hb=f05128e0aee9894a93455dd425ed6104a90a3999;hpb=d474c27d3c37b00d2b2ec2dc62d123d69c8edac9
diff --git a/src/edu/berkeley/sbp/meta/GrammarAST.java b/src/edu/berkeley/sbp/meta/GrammarAST.java
index 297886b..0b4ba07 100644
--- a/src/edu/berkeley/sbp/meta/GrammarAST.java
+++ b/src/edu/berkeley/sbp/meta/GrammarAST.java
@@ -16,12 +16,16 @@ import java.io.*;
*/
public class GrammarAST {
+ public static interface ImportResolver {
+ public InputStream getImportStream(String importname);
+ }
+
/**
* Returns a Union representing the metagrammar (meta.g); the Tree produced by
* parsing with this Union should be provided to buildFromAST
*/
public static Union getMetaGrammar() {
- return buildFromAST(MetaGrammar.meta, "s", new File[0]);
+ return buildFromAST(MetaGrammar.meta, "s", null);
}
/**
@@ -31,8 +35,17 @@ public class GrammarAST {
* @param s the name of the "start symbol"
* @param gbr a GrammarBindingResolver that resolves grammatical reductions into tree-node-heads
*/
- public static Union buildFromAST(Tree grammarAST, String startingNonterminal, File[] includes) {
- return new GrammarAST(includes, "").buildGrammar(grammarAST, startingNonterminal);
+ public static Union buildFromAST(Tree grammarAST, String startingNonterminal, ImportResolver resolver) {
+ return new GrammarAST(resolver, "").buildGrammar(grammarAST, startingNonterminal);
+ }
+
+ /** This does not work yet */
+ public static void emitCode(PrintWriter pw, Tree grammarAST, String startingNonterminal, ImportResolver resolver) {
+ GrammarAST ga = new GrammarAST(resolver, "");
+ Object o = ga.walk(grammarAST);
+ GrammarAST.GrammarNode gn = (GrammarAST.GrammarNode)o;
+ EmitContext ecx = ga.new EmitContext(gn);
+ gn.emitCode(ecx, pw, "com.foo", "ClassName");
}
private static Object illegalTag = ""; // this is the tag that should never appear in the non-dropped output FIXME
@@ -40,11 +53,11 @@ public class GrammarAST {
// Instance //////////////////////////////////////////////////////////////////////////////
private final String prefix;
- private final File[] includes;
+ private final ImportResolver resolver;
- public GrammarAST(File[] includes, String prefix) {
+ public GrammarAST(ImportResolver resolver, String prefix) {
this.prefix = prefix;
- this.includes = includes;
+ this.resolver = resolver;
}
// Methods //////////////////////////////////////////////////////////////////////////////
@@ -92,6 +105,7 @@ public class GrammarAST {
if (head.equals("Elements")) return new Seq((ElementNode[])Reflection.rebuild(walkChildren(t), ElementNode[].class));
if (head.equals("NonTerminalReference")) return new ReferenceNode(stringifyChildren(t.child(0)));
if (head.equals(")")) return new ReferenceNode(stringifyChildren(t.child(0)), true);
+ if (head.equals(":")) return new LabelNode(stringifyChildren(t.child(0)), walkElement(t.child(1)));
if (head.equals("::")) return walkSeq(t.child(1)).tag(walkString(t.child(0)));
if (head.equals("...")) return new DropNode(new RepeatNode(new TildeNode(new AtomNode()), null, true, true, false));
@@ -111,9 +125,9 @@ public class GrammarAST {
if (head.equals("Quoted")) return stringifyChildren(t);
if (head.equals("Literal")) return new LiteralNode(walkString(t.child(0)));
if (head.equals("->")) return walkSeq(t.child(0)).follow(walkElement(t.child(1)));
- if (head.equals("DropNT")) return new NonTerminalNode(walkString(t.child(0)), (Seq[][])walkChildren(t.child(1)), false, null, true);
+ if (head.equals("DropNT")) return new NonTerminalNode(walkString(t.child(0)), (Seq[][])walkChildren(t.child(1)), false, null, true, false);
if (head.equals("=")) return new NonTerminalNode(walkString(t.child(0)), (Seq[][])walk(t.child(2)),
- true, t.size()==2 ? null : walkString(t.child(1)), false);
+ true, t.size()==2 ? null : walkString(t.child(1)), false, false);
if (head.equals("&")) return walkSeq(t.child(0)).and(walkSeq(t.child(1)));
if (head.equals("&~")) return walkSeq(t.child(0)).andnot(walkSeq(t.child(1)));
if (head.equals("/")) return (walkSeq(t.child(0))).separate(walkElement(t.child(1)));
@@ -133,34 +147,36 @@ public class GrammarAST {
}
if (head.equals("\"\"")) return "";
if (head.equals("\n")) return "\n";
+ if (head.equals("\t")) return "\t";
if (head.equals("\r")) return "\r";
- if (head.equals("SubGrammar")) return GrammarAST.buildFromAST(t.child(0), "s", includes);
+ if (head.equals("SubGrammar")) return GrammarAST.buildFromAST(t.child(0), "s", resolver);
if (head.equals("NonTerminal"))
return new NonTerminalNode(walkString(t.child(0)),
- (Seq[][])walkChildren(t.child(1)), false, null, false);
+ (Seq[][])walkChildren(t.child(1)), false, null, false, false);
if (head.equals("Colons")) {
String tag = walkString(t.child(0));
Seq[][] seqs = (Seq[][])walk(t.child(1));
for(Seq[] seq : seqs)
for(int i=0; i " + (head.equals("...")));
}
@@ -198,113 +214,95 @@ public class GrammarAST {
return ret + " ]";
}
public Union build(String rootNonterminal) {
- Context cx = new Context(this);
+ BuildContext cx = new BuildContext(this);
Union u = null;
for(GrammarAST.NonTerminalNode nt : values())
if (nt.name.equals(rootNonterminal))
return (Union)cx.get(nt.name);
return null;
}
- }
-
- /** a node in the AST which is resolved into an Element */
- private abstract class ElementNode {
- public boolean isLifted() { return false; }
- public boolean drop(Context cx) { return false; }
- public Atom toAtom(Context cx) { throw new Error("can't convert a " + this.getClass().getName() + " to an atom: " + this); }
- public abstract Element build(Context cx, NonTerminalNode cnt, boolean dropall);
- }
-
- private class UnionNode extends ElementNode {
- public Seq[][] sequences;
- public String sep = null;
- public boolean rep;
- public UnionNode(Seq seq) { this(new Seq[][] { new Seq[] { seq } }); }
- public UnionNode(Seq[][] sequences) { this(sequences, false, null); }
- public UnionNode(Seq[][] sequences, boolean rep, String sep) {
- this.sequences = sequences;
- this.rep = rep;
- this.sep = sep;
- }
- public boolean drop(Context cx) {
- for(Seq[] seqs : sequences)
- for(Seq seq : seqs)
- if (!seq.drop(cx))
- return false;
- return true;
- }
- public Atom toAtom(Context cx) {
- Atom ret = null;
- for(Seq[] ss : sequences)
- for(Seq s : ss)
- ret = ret==null ? s.toAtom(cx) : (Atom)ret.union(s.toAtom(cx));
- return ret;
- }
- public Element build(Context cx, NonTerminalNode cnt, boolean dropall) {
- return buildIntoPreallocatedUnion(cx, cnt, dropall, new Union(null, false)); }
- public Element buildIntoPreallocatedUnion(Context cx, NonTerminalNode cnt, boolean dropall, Union u) {
- Union urep = null;
- if (rep) {
- urep = new Union(null, false);
- urep.add(Sequence.create(cnt.name, new Element[0]));
- urep.add(sep==null
- ? Sequence.create(new Element[] { u }, 0)
- : Sequence.create(new Element[] { cx.get(sep), u }, 1));
- }
- HashSet bad2 = new HashSet();
- for(int i=0; i= 'A' && nt.name.charAt(0) <= 'Z')) continue;
+ StringBuffer fieldDeclarations = new StringBuffer();
+ StringBuffer walkCode = new StringBuffer();
+ nt.getUnionNode().emitCode(cx, fieldDeclarations, walkCode);
+ if (nt.tagged) {
+ pw.println(" public static class " + nt.name + "{");
+ pw.println(fieldDeclarations);
+ pw.println(" }");
+ pw.println(" public static " + nt.name + " walk"+nt.name+"(Tree t) {");
+ pw.println(" int i = 0;");
+ pw.println(walkCode);
+ pw.println(" }");
+ } else {
+ // FIXME; list who extends it
+ pw.println(" public static interface " + nt.name + "{ }");
+ // FIXME: what on earth is this going to be?
+ pw.println(" public static " + nt.name + " walk"+nt.name+"(Tree t) {");
+ pw.println(" throw new Error(\"FIXME\");");
+ pw.println(" }");
+ }
}
- return u;
+ pw.println("}");
}
}
- private class NonTerminalNode extends UnionNode {
- public boolean alwaysDrop;
- public String name = null;
- public boolean drop(Context cx) { return alwaysDrop; }
- public NonTerminalNode(String name, Seq[][] sequences, boolean rep, String sep, boolean alwaysDrop) {
- super(sequences, rep, sep==null?null:(prefix + sep));
+ /** a NonTerminal is always a union at the top level */
+ private class NonTerminalNode {
+ public final boolean alwaysDrop;
+ public final String name;
+ public final ElementNode elementNode;
+ public final UnionNode unionNode;
+ public final boolean tagged;
+ public NonTerminalNode(String name, Seq[][] sequences, boolean rep, String sep, boolean alwaysDrop, boolean tagged) {
this.name = prefix + name;
this.alwaysDrop = alwaysDrop;
+ this.tagged = tagged;
+ this.unionNode = new UnionNode(sequences, rep, sep==null?null:(prefix + sep));
+ this.elementNode = alwaysDrop ? new DropNode(unionNode) : unionNode;
}
- public Element build(Context cx, NonTerminalNode cnt, boolean dropall) { return cx.get(name); }
+ public boolean isDropped(Context cx) { return alwaysDrop; }
+ public Element build(BuildContext cx, NonTerminalNode cnt, boolean dropall) { return cx.get(name); }
+ public ElementNode getElementNode() { return elementNode; }
+ public UnionNode getUnionNode() { return unionNode; }
}
+ /** a sequence */
private class Seq {
+ /** elements of the sequence */
+ ElementNode[] elements;
+ /** follow-set, if explicit */
+ ElementNode follow;
+ /** tag to add when building the AST */
+ String tag = null;
+ /** positive conjuncts */
+ HashSet and = new HashSet();
+ /** negative conjuncts */
+ HashSet not = new HashSet();
public boolean alwaysDrop = false;
- public boolean drop(Context cx) {
+
+ public boolean isTagless() {
+ if (alwaysDrop) return true;
+ for(int i=0; i and = new HashSet();
- HashSet not = new HashSet();
- ElementNode[] elements;
- ElementNode follow;
- String tag = null;
public Seq(ElementNode e) { this(new ElementNode[] { e }); }
public Seq(ElementNode[] elements) { this(elements, true); }
public Seq(ElementNode[] el, boolean check) {
@@ -333,7 +331,7 @@ public class GrammarAST {
}
}
}
- public Atom toAtom(Context cx) {
+ public Atom toAtom(BuildContext cx) {
if (elements.length != 1)
throw new Error("you attempted to use ->, **, ++, or a similar character-class"+
" operator on a [potentially] multicharacter production");
@@ -353,20 +351,20 @@ public class GrammarAST {
this.elements = elements;
return this;
}
- public Sequence build(Context cx, Union u, NonTerminalNode cnt, boolean dropall) {
+ public Sequence build(BuildContext cx, Union u, NonTerminalNode cnt, boolean dropall) {
Sequence ret = build0(cx, cnt, dropall);
for(Seq s : and) ret = ret.and(s.build(cx, null, cnt, true));
for(Seq s : not) ret = ret.andnot(s.build(cx, null, cnt, true));
if (u!=null) u.add(ret);
return ret;
}
- public Sequence build0(Context cx, NonTerminalNode cnt, boolean dropall) {
+ public Sequence build0(BuildContext cx, NonTerminalNode cnt, boolean dropall) {
boolean[] drops = new boolean[elements.length];
Element[] els = new Element[elements.length];
- dropall |= drop(cx);
+ dropall |= isDropped(cx);
for(int i=0; i cl = new HashSet ();
+ for(Seq[] ss : sequences)
+ for(Seq s : ss) {
+ /*
+ String cls = s.getEmitClass();
+ if (cls != null) cl.add(cls);
+ */
+ }
+ return (String[])cl.toArray(new String[0]);
+ }
+
+ public void _emitCode(EmitContext cx,
+ StringBuffer fieldDeclarations,
+ StringBuffer walkCode) {
+ throw new RuntimeException("not implemented " + this.getClass().getName());
+ }
+
+ public String getFieldName() { return null; }
+ public boolean isLifted() { return false; }
+ public boolean isDropped(Context cx) {
+ for(Seq[] seqs : sequences)
+ for(Seq seq : seqs)
+ if (!seq.isDropped(cx))
+ return false;
+ return true;
+ }
+ public Atom toAtom(BuildContext cx) {
+ Atom ret = null;
+ for(Seq[] ss : sequences)
+ for(Seq s : ss)
+ ret = ret==null ? s.toAtom(cx) : (Atom)ret.union(s.toAtom(cx));
+ return ret;
+ }
+
+ public Element build(BuildContext cx, NonTerminalNode cnt, boolean dropall) {
+ return buildIntoPreallocatedUnion(cx, cnt, dropall, new Union(null, false)); }
+ public Element buildIntoPreallocatedUnion(BuildContext cx, NonTerminalNode cnt, boolean dropall, Union u) {
+ Union urep = null;
+ if (rep) {
+ urep = new Union(null, false);
+ urep.add(Sequence.create(cnt.name, new Element[0]));
+ urep.add(sep==null
+ ? Sequence.create(new Element[] { u }, 0)
+ : Sequence.create(new Element[] { cx.get(sep), u }, 1));
+ }
+ HashSet bad2 = new HashSet();
+ for(int i=0; i)_e.toAtom(cx).complement()); }
- public Element build(Context cx, NonTerminalNode cnt, boolean dropall) { return toAtom(cx); }
+ public Atom toAtom(BuildContext cx) { return (Atom)((Topology)_e.toAtom(cx).complement()); }
+ public Element build(BuildContext cx, NonTerminalNode cnt, boolean dropall) { return toAtom(cx); }
}
private class DropNode extends ElementNodeWrapper {
public DropNode(ElementNode e) { super(e); }
- public boolean drop(Context cx) { return true; }
+ public boolean isDropped(Context cx) { return true; }
+ }
+
+ /** provides a label on the fields of a Seq */
+ private class LabelNode extends ElementNodeWrapper {
+ public final String label;
+ public LabelNode(String label, ElementNode e) { super(e); this.label = label; }
+ public String getFieldName() { return label; }
}
//////////////////////////////////////////////////////////////////////////////
@@ -523,8 +674,18 @@ public class GrammarAST {
public class Context {
public HashMap map = new HashMap();
public GrammarNode grammar;
- public Context(Tree t) { }
+ public Context() { }
public Context(GrammarNode g) { this.grammar = g; }
+ }
+
+
+ public class EmitContext extends Context {
+ public EmitContext(GrammarNode g) { super(g); }
+ }
+
+ public class BuildContext extends Context {
+ public BuildContext(Tree t) { }
+ public BuildContext(GrammarNode g) { super(g); }
public Union build() {
Union ret = null;
for(NonTerminalNode nt : grammar.values()) {
@@ -545,7 +706,7 @@ public class GrammarAST {
} else {
ret = new Union(name, false);
map.put(name, ret);
- nt.buildIntoPreallocatedUnion(this, nt, nt.drop(this), ret);
+ nt.getUnionNode().buildIntoPreallocatedUnion(this, nt, nt.isDropped(this), ret);
}
return ret;
}