_____________________________________________________________________________
Immediately
- - Performance
- - hash Long->long: it's all bogus
-
* pick back up cleaning up end of Parser.java (Reduction)
- [more] sensible tree-printout
--- /dev/null
+package edu.berkeley.sbp;
+import edu.berkeley.sbp.*;
+import edu.berkeley.sbp.util.*;
+import edu.berkeley.sbp.Sequence.Position;
+import java.io.*;
+import java.util.*;
+
+/** if ambiguity checking is enabled, this exception is thrown to signal that the parse was ambiguous */
+public class Ambiguous extends RuntimeException {
+ public final Forest ambiguity;
+ public Ambiguous(Forest ambiguity) { this.ambiguity = ambiguity; }
+ public String toString() {
+ StringBuffer sb = new StringBuffer();
+ sb.append("unresolved ambiguity "/*"at " + ambiguity.getLocation() + ":"*/);
+ for(Object result : ambiguity.expand(false))
+ sb.append("\n " + result);
+ return sb.toString();
+ }
+}
public abstract class Forest<T> {
/** assume that this forest contains exactly one tree and return it; otherwise throw an exception */
- public final Tree<T> expand1() throws Parser.Ambiguous, Parser.Failed {
+ public final Tree<T> expand1() throws Ambiguous, ParseFailed {
Iterator<Tree<T>> it = expand(true).iterator();
- if (!it.hasNext()) throw new Parser.Failed();
+ if (!it.hasNext()) throw new ParseFailed();
return it.next();
}
HashSet<Tree<T>> ret = new HashSet<Tree<T>>();
for(Body<T> b : results)
ret.addAll(b.expand(toss, new ArrayList<Tree<T>>(), 0, new HashSet<Tree<T>>()));
- if (toss && ret.size() > 1) throw new Parser.Ambiguous(this);
+ if (toss && ret.size() > 1) throw new Ambiguous(this);
return ret;
}
return ret.toString();
}
- public boolean isDone() throws Parser.Failed {
+ public boolean isDone() throws ParseFailed {
if (token != null) return false;
if (token==null && finalResult==null)
- throw new Parser.Failed(error(red("unexpected end of file\n")),
+ throw new ParseFailed(error(red("unexpected end of file\n")),
getLocation());
return true;
}
}
/** perform all shift operations, adding promoted nodes to <tt>next</tt> */
- public void shift(Phase next, Forest result) throws Parser.Failed {
+ public void shift(Phase next, Forest result) throws ParseFailed {
if (prev!=null) prev.hash = null;
this.next = next;
closed = true;
}
if (!good && token!=null)
- throw new Parser.Failed(error(red("unexpected character")+" "+purple(token)+" encountered at "+green(getLocation())+"\n"),
+ throw new ParseFailed(error(red("unexpected character")+" "+purple(token)+" encountered at "+green(getLocation())+"\n"),
getLocation());
if (token==null && finalResult==null)
- throw new Parser.Failed(error(red("unexpected end of file\n")),
+ throw new ParseFailed(error(red("unexpected end of file\n")),
getLocation());
// this massively improves GC performance
--- /dev/null
+package edu.berkeley.sbp;
+import edu.berkeley.sbp.*;
+import edu.berkeley.sbp.util.*;
+import java.io.*;
+import java.util.*;
+
+/** thrown when the parser arrives at a state from which it is clear that no valid parse can result */
+public class ParseFailed extends RuntimeException {
+ private final Token.Location location;
+ private final String message;
+ public ParseFailed() { this("", null); }
+ public ParseFailed(String message, Token.Location loc) { this.location = loc; this.message = message; }
+ public Token.Location getLocation() { return location; }
+ public String toString() { return message/* + (location==null ? "" : (" at " + location))*/; }
+}
package edu.berkeley.sbp;
import edu.berkeley.sbp.*;
import edu.berkeley.sbp.util.*;
-import edu.berkeley.sbp.*;
import edu.berkeley.sbp.Sequence.Position;
-import edu.berkeley.sbp.*;
import java.io.*;
import java.util.*;
-import java.lang.reflect.*;
/** a parser which translates streams of Tokens of type T into a Forest<R> */
public abstract class Parser<T extends Token, R> {
- public final Table pt;
+ private final Table pt;
/** create a parser to parse the grammar with start symbol <tt>u</tt> */
protected Parser(Union u) { this.pt = new Table(u, top()); }
- protected Parser(Table pt) { this.pt = pt; }
+ //protected Parser(Table pt) { this.pt = pt; }
+ /** implement this method to create the output forest corresponding to a lone shifted input token */
public abstract Forest<R> shiftedToken(T t, Token.Location loc);
- public abstract Topology<T> top();
+ /** this method must return an empty topology of the input token type */
+ public abstract Topology<T> top();
- /** parse <tt>input</tt> for a exactly one unique result, throwing <tt>Ambiguous</tt> if not unique or <tt>Failed</tt> if none */
- public Tree<R> parse1(Token.Stream<T> input) throws IOException, Failed, Ambiguous {
+ /** parse <tt>input</tt> for a exactly one unique result, throwing <tt>Ambiguous</tt> if not unique or <tt>ParseFailed</tt> if none */
+ public Tree<R> parse1(Token.Stream<T> input) throws IOException, ParseFailed, Ambiguous {
Forest<R> ret = parse(input);
try { return ret.expand1(); }
catch (Ambiguous a) {
}
/** parse <tt>input</tt>, using the table <tt>pt</tt> to drive the parser */
- public Forest<R> parse(Token.Stream<T> input) throws IOException, Failed {
+ public Forest<R> parse(Token.Stream<T> input) throws IOException, ParseFailed {
GSS gss = new GSS();
Token.Location loc = input.getLocation();
GSS.Phase current = gss.new Phase(null, this, null, input.next(1, 0, 0), loc, null);
// Exceptions //////////////////////////////////////////////////////////////////////////////
- public static class Failed extends RuntimeException {
- private final Token.Location location;
- private final String message;
- public Failed() { this("", null); }
- public Failed(String message, Token.Location loc) { this.location = loc; this.message = message; }
- public Token.Location getLocation() { return location; }
- public String toString() { return message/* + (location==null ? "" : (" at " + location))*/; }
- }
-
- public static class Ambiguous extends RuntimeException {
- public final Forest ambiguity;
- public Ambiguous(Forest ambiguity) { this.ambiguity = ambiguity; }
- public String toString() {
- StringBuffer sb = new StringBuffer();
- sb.append("unresolved ambiguity "/*"at " + ambiguity.getLocation() + ":"*/);
- for(Object result : ambiguity.expand(false))
- sb.append("\n " + result);
- return sb.toString();
- }
- }
-
// Table //////////////////////////////////////////////////////////////////////////////
}
public boolean execute() throws Exception {
Forest<String> res = null;
- Parser.Failed pfe = null;
+ ParseFailed pfe = null;
try {
res = new CharToken.CharToStringParser(grammar).parse(inp);
- } catch (Parser.Failed pf) {
+ } catch (ParseFailed pf) {
pfe = pf;
}
//ystem.out.println("res=="+res);
package edu.berkeley.sbp.util;
import java.util.*;
-/** a mapping from keys of type <tt>K</tt> to <i>sets</i> of values of type <tt>T</tt> */
+// FEATURE: make this faster (plenty of ways: quadradic probing hash table is one)
+/** a sparse mapping from pairs of <tt>int</tt>'s to <tt>V</tt>'s */
public final class IntPairMap<V> {
private final HashMap<Long, V> hm = new HashMap<Long, V>();