checkpoint
[sbp.git] / src / edu / berkeley / sbp / Parser.java
index dc6c1f6..817aea6 100644 (file)
@@ -184,7 +184,7 @@ public abstract class Parser<T extends Token, R> {
             public boolean             canShift(Token t)           { return shifts.contains(t); }
             public Iterable<State>     getShifts(Token t)          { return shifts.get(t); }
             public boolean             isAccepting()               { return accept; }
-            public Iterable<Reduction> getReductions(Token t)      { return reductions.get(t); }
+            public Iterable<Reduction> getReductions(Token t)      { return t==null ? eofReductions : reductions.get(t); }
             public Iterable<Reduction> getEofReductions()          { return eofReductions; }
             public Iterator<Position>  iterator()                  { return hs.iterator(); }
 
@@ -311,11 +311,25 @@ public abstract class Parser<T extends Token, R> {
             }
             public String toString() { return "[reduce " + position + "]"; }
 
-            public Forest reduce(GSS.Phase.Node parent, GSS.Phase.Node onlychild, Forest rex) {
-                Forest ret = reduce(parent, numPop-1, rex, onlychild, parent.phase());
+            public Forest reduce(GSS.Phase.Node parent) {
+                Forest rex = numPop==0 ? zero() : null;
+                Forest ret = reduce(parent, numPop-1, rex, null, parent.phase());
                 return ret;
             }
 
+            public Forest reduce(GSS.Phase.Node parent, GSS.Phase.Node onlychild) {
+                int pos = numPop-1;
+                if (pos>=0) holder[pos] = parent.pending();
+                Forest rex = null;
+                if (pos==0) {
+                    if (rex==null) {
+                        System.arraycopy(holder, 0, position.holder, 0, holder.length);
+                        rex = position.rewrite(parent.phase().getLocation());
+                    }
+                }
+                return reduce(onlychild, pos-1, rex, null, parent.phase());
+            }
+
             private Forest zero = null;
             public Forest zero() {
                 if (zero != null) return zero;