X-Git-Url: http://git.megacz.com/?p=sbp.git;a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2FParser.java;h=08c49a9aeb34e6ff684dead960bd40e8afba51bc;hp=65f3dc3e9e3f17b80be3d03950ffc9d22ddc0901;hb=d5f34dfd50f82d7647d2ce2d014ae83e07d8280a;hpb=b0ec1efcb13eceb539f9cd033a0d2908fc2be27a

diff --git a/src/edu/berkeley/sbp/Parser.java b/src/edu/berkeley/sbp/Parser.java
index 65f3dc3..08c49a9 100644
--- a/src/edu/berkeley/sbp/Parser.java
+++ b/src/edu/berkeley/sbp/Parser.java
@@ -311,6 +311,13 @@ public abstract class Parser<T extends Token, R> {
             }
             public String toString() { return "[reduce " + position + "]"; }
 
+            private Forest zero = null;
+            public Forest zero() {
+                if (zero != null) return zero;
+                if (numPop > 0) throw new Error();
+                return zero = position.rewrite(null);
+            }
+
             public Forest reduce(GSS.Phase.Node parent) {
                 if (numPop==0) return finish(parent, zero(), parent.phase());
                 return reduce(parent, numPop-1, null, parent.phase());
@@ -320,21 +327,11 @@ public abstract class Parser<T extends Token, R> {
                 if (numPop<=0) throw new Error("called wrong form of reduce()");
                 int pos = numPop-1;
                 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());
-                    }
+                    System.arraycopy(holder, 0, position.holder, 0, holder.length);
+                    return finish(onlychild, position.rewrite(parent.phase().getLocation()), parent.phase());
                 }
-                return reduce(onlychild, pos-1, rex, parent.phase());
-            }
-
-            private Forest zero = null;
-            public Forest zero() {
-                if (zero != null) return zero;
-                if (numPop > 0) throw new Error();
-                return zero = position.rewrite(null);
+                return reduce(onlychild, pos-1, null, parent.phase());
             }
 
             // FIXME: this could be more elegant and/or cleaner and/or somewhere else
@@ -346,7 +343,8 @@ public abstract class Parser<T extends Token, R> {
                     rex = position.rewrite(target.getLocation());
                 }
                 for(GSS.Phase.Node child : parent.parents())
-                    reduce(child, pos-1, rex, target);
+                    if (pos==0) finish(child, rex, target);
+                    else reduce(child, pos-1, rex, target);
                 return rex;
             }
             private Forest finish(GSS.Phase.Node parent, Forest result, GSS.Phase target) {