refactored error reporting
[sbp.git] / src / edu / berkeley / sbp / GSS.java
index cff543d..d2b040d 100644 (file)
@@ -17,43 +17,32 @@ class GSS {
     public int resets = 0;
     public int waits = 0;
 
-    HashMapBag<Integer,Sequence> inhibited = new HashMapBag<Integer,Sequence>();
-    HashMapBag<Integer,Sequence> assumed = new HashMapBag<Integer,Sequence>();
+    HashMapBag<Integer,Sequence>       inhibited = new HashMapBag<Integer,Sequence>();
     HashMapBag<Sequence,Phase.Waiting> waiting   = new HashMapBag<Sequence,Phase.Waiting>();
-    HashMapBag<Integer,Sequence> performed = new HashMapBag<Integer,Sequence>();
-    HashSet<Phase.Waiting> tail = new     HashSet<Phase.Waiting>();
+    HashMapBag<Integer,Sequence>       performed = new HashMapBag<Integer,Sequence>();
     
+    /** FIXME */
+    public  Forest.Ref finalResult;
+
     /** corresponds to a positions <i>between tokens</i> the input stream; same as Tomita's U_i's */
     public class Phase implements Invokable<State, Forest, GSS.Phase.Node>, IntegerMappable {
-        public int toInt() { return pos+1; }
 
         /** the token immediately after this phase */
-        public  final Token token;
-
-        boolean reducing;
+        final Token token;
 
-        /** currently this is necessary only for the code() hack -- it doesn't actually correspond to the input */
         private final int pos;
 
-        /** FIXME */
-        public  Forest.Ref finalResult;
-
-        /** all nodes, keyed by the value returned by code() */
-        /*private*/ IntPairMap<Phase.Node> hash;  /* ALLOC */
-
-        /** the number of nodes in this phase */
-        private int numNodes;
-
-        boolean closed;
-
+        boolean reducing;
+        private IntPairMap<Phase.Node> hash;  /* ALLOC */
+        private boolean closed;
         private boolean good;
         private Phase next = null;
-
+        private Phase prev;
         private Token.Location location;
         public final Parser parser;
 
         private Forest forest;
-        Phase prev;
+
         public Phase(Phase prev, Parser parser, Phase previous, Token token, Token.Location location, Forest forest) {
             this.prev = prev;
             this.forest = forest;
@@ -62,103 +51,25 @@ class GSS {
             this.token = token;
             this.location = location;
             inhibited.clear();
-            assumed.clear();
             reset();
         }
 
         public void reset() {
-            tail.clear();
             waiting.clear();
             performed.clear();
             hash = new IntPairMap<Phase.Node>();
             good = false;
             closed = false;
-            numNodes = 0;
             reducing = false;
             finalResult = null;
             if (prev != null) prev.shift(this, forest);
         }
 
-        public void complain(Node n, HashMap<String,HashSet<String>> errors, boolean force) {
-            if (n.touched) return;
-            n.touched = true;
-            for(Position p : n.state) {
-                //if (!p.isLast()) { 
-                if (((p.isFirst() || p.isLast()) && !force) || p.owner().name==null) {
-                    for(Node n2 : n.parents())
-                        complain(n2, errors, force | p.isFirst());
-                } else {
-                    String seqname = p.owner().name;
-                    HashSet<String> hs = errors.get(seqname);
-                    if (hs==null) errors.put(seqname, hs = new HashSet<String>());
-                    hs.add(p.element()+"");
-                    //String s = "  while parsing " + seqname + ": expected a " + p.element();
-                        //"\n";
-                    /*
-                    s +=       "      parsed: ";
-                    for(Position p2 = p.owner().firstp(); p2 != null && p2 != p && !p2.isLast(); p2 = p2.next()) s += (p2.element() + " ");
-                    s += "\n";
-                    s +=       "    expected: ";
-                    for(Position p2 = p; p2 != null && !p2.isLast(); p2 = p2.next()) s += (p2.element() + " ");
-                    */
-                    //s += "\n";
-                    //errors.add(s);
-                }
-            }
-        }
-
-        public String black(Object o) { return "\033[30m"+o+"\033[0m"; }
-        public String red(Object o) { return "\033[31m"+o+"\033[0m"; }
-        public String green(Object o) { return "\033[32m"+o+"\033[0m"; }
-        public String yellow(Object o) { return "\033[33m"+o+"\033[0m"; }
-        public String blue(Object o) { return "\033[34m"+o+"\033[0m"; }
-        public String purple(Object o) { return "\033[35m"+o+"\033[0m"; }
-        public String cyan(Object o) { return "\033[36m"+o+"\033[0m"; }
-        public String el(Object e) {
-            String s = e.toString();
-            if (s.length()==0 || s.charAt(0)!='\"' || s.charAt(s.length()-1)!='\"') return yellow(s);
-            s = s.substring(1);
-            s = s.substring(0, s.length()-1);
-            StringBuffer ret = new StringBuffer();
-            for(int i=0; i<s.length(); i++) {
-                if (s.charAt(i)=='\\' && i<s.length()-1) ret.append(s.charAt(++i));
-                else ret.append(s);
-            }
-            return purple(ret.toString());
-        }
-        public String error(String message) {
-            String lookAhead = token==null ? "<EOF>" : token.toString();
-            StringBuffer ret = new StringBuffer();
-            ret.append("\n  ");
-            ret.append(message);
-            HashMap<String,HashSet<String>> errors = new HashMap<String,HashSet<String>>();
-            for(Node n : hash.values()) {
-                //System.out.println(n.state);
-                complain(n, errors, false);
-            }
-            for(String s : errors.keySet()) {
-                ret.append("    while parsing " + yellow(s));
-                HashSet<String> hs = errors.get(s);
-                if (hs.size()==1) ret.append(" expected " + yellow(el(hs.iterator().next())) + "\n");
-                else {
-                    ret.append(" expected ");
-                    boolean first = true;
-                    for(String s2 : hs) {
-                        if (!first) ret.append(" or ");
-                        first = false;
-                        ret.append(yellow(el(s2)));
-                    }
-                    ret.append("\n");
-                }
-            }
-            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")),
-                                        getLocation());
+                throw new ParseFailed(ParseFailed.error(ANSI.red("unexpected end of file\n"), token, hash.values()), getLocation());
             return true;
         }
 
@@ -181,12 +92,6 @@ class GSS {
             Sequence owner = reduction==null ? null : reduction.position.owner();
             if (reduction!=null) {
                 if (inhibited.contains(pos, owner)) return;
-                /*
-                if (assumed.contains(pos, owner)) {
-                    tail.add(new Waiting(parent, pending, state, fromEmptyReduction, reduction));
-                    return;
-                }
-                */
                 if (owner.needs != null)
                     for(Sequence s : owner.needs)
                         if (!performed.contains(pos, s)) {
@@ -228,7 +133,7 @@ class GSS {
                 if (token != null && state.canShift(token)) break;
                 if (state.isAccepting()) break;
                 if (token==null) break;
-                //if (!state.canReduce(token)) return false;
+                if (!state.canReduce(token)) return false;
                 //if (count > 1) break;
                 //if (r.numPop == 0) break;
                 //r.reduce(pending, parent, null, Phase.this, null);
@@ -257,7 +162,6 @@ class GSS {
                     //System.out.println("\nresetting due to " + r.position.owner() + " killing " + seq);
                     //inhibited.clear();
                     inhibited.add(p, seq);
-                    //assumed = inhibited;
                     //inhibited = new HashMapBag<Integer,Sequence>();
                     reset = true;
                     resets++;
@@ -285,8 +189,6 @@ class GSS {
                     reducing_list[i] = null;
                     n.queueReductions();
                 }
-                //for(Waiting w : tail)
-                //w.perform();
             } catch (Reset r) {
                 reset();
                 reduce();
@@ -296,15 +198,12 @@ class GSS {
         class Reset extends RuntimeException { }
 
         public void invoke(State st, Forest result, Node n) {
-            boolean ok = next.newNode(n, result, st, false);
-            if (ok && !good) {
-                good = !st.lame();
-                //if (good) System.out.println(st);
-            }
+            good |= next.newNode(n, result, st, false);
         }
 
         /** 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 {
+            // this massively improves GC performance
             if (prev!=null) prev.hash = null;
             this.next = next;
             closed = true;
@@ -320,14 +219,11 @@ class GSS {
             }
 
             if (!good && token!=null)
-                throw new Parser.Failed(error(red("unexpected character")+" "+purple(token)+" encountered at "+green(getLocation())+"\n"),
+                throw new ParseFailed(ParseFailed.error(ANSI.red("unexpected character")+" "+ANSI.purple(token)+" encountered at "+ANSI.green(getLocation())+"\n", token, hash.values()),
                                         getLocation());
             if (token==null && finalResult==null)
-                throw new Parser.Failed(error(red("unexpected end of file\n")),
+                throw new ParseFailed(ParseFailed.error(ANSI.red("unexpected end of file\n"), token, hash.values()),
                                         getLocation());
-
-            // this massively improves GC performance
-            //hash = null;
         }
 
 
@@ -385,10 +281,10 @@ class GSS {
 
             public final void invoke(Reduction r, Node n, Node n2) {
                 if (n==null) {
-                    if (r.numPop==0) r.reduce(this);
+                    if (r.position.pos==0) r.reduce(this);
                     return;
                 }
-                if (r.numPop==0) return;
+                if (r.position.pos==0) return;
                 if (n2==null) r.reduce(n);
                 else          r.reduce(n, n2);
             }
@@ -408,16 +304,11 @@ class GSS {
                 if (parent != null) parents().add(parent, true);
                 if (Phase.this.hash.get(state, start) != null) throw new Error("severe problem!");
                 Phase.this.hash.put(state, start, this);
-                Phase.this.numNodes++;
             }
         }
 
+        public int toInt() { return pos+1; }
+        public int size() { return hash==null ? 0 : hash.size(); }
     }
 
-    /** helper method */
-    private static boolean equal(Object a, Object b) {
-        if (a==null && b==null) return true;
-        if (a==null || b==null) return false;
-        return a.equals(b);
-    }
 }