change naming: use pred/succ rather than parent/child

[sbp.git] / src / edu / berkeley / sbp / Node.java

diff --git a/src/edu/berkeley/sbp/Node.java b/src/edu/berkeley/sbp/Node.java
index 100f89f..ccc2516 100644 (file)
--- a/src/edu/berkeley/sbp/Node.java
+++ b/src/edu/berkeley/sbp/Node.java
@@ -29,31 +29,31 @@ final class Node
     public void check() {
         if (destroyed) return;
         boolean dead = true;
-        // - all nodes must have a parent
+        // - all nodes must have a predecessor
         // - non-doomed nodes must either:
         //      - be on the frontier or
         //      - have a non-doomed node closer to the frontier than themself
         if (phase.isFrontier()) dead = false;
-        else for(Result r : children)
+        else for(Result r : successors)
                  if (state.doomed) { if (r.usedByAnyNode()) { dead = false; break; } }
                  else              { if (r.usedByNonDoomedNode()) { dead = false; break; } }
         dead |= results.size()==0;
         if (!dead) return;
         destroyed = true;
-        while(children.size()>0)
-            for(Result r : children) {
-                children.remove(r);
+        while(successors.size()>0)
+            for(Result r : successors) {
+                successors.remove(r);
                 r.destroy();
                 break;
             }
         while(results.size()>0)
             for(Result r : results) {
                 results.remove(r);
-                r.removeChild(this);
+                r.removeSucc(this);
                 break;
             }
         results = null;
-        children = null;
+        successors = null;
     }
 
     //////////////////////////////////////////////////////////////////////
@@ -66,7 +66,7 @@ final class Node
     private final boolean fromEmptyReduction;
     //private       FastSet<Result> results = new FastSet<Result>();
     private       HashSet<Result> results = new HashSet<Result>();
-    private       HashSet<Result> children = new HashSet<Result>();
+    private       HashSet<Result> successors = new HashSet<Result>();
 
     public final void invoke(Pos r, Result only) {
         boolean emptyProductions = only==null;
@@ -84,12 +84,12 @@ final class Node
         if (results==null) return;   // FIXME: this should not happen
         for(Result res : results)
             if (only == null || res == only) {
-                Node child = res.parent();
+                Node pred = res.pred();
                 holder[pos] = res.getForest();
-                if (pos>0)  child.reduce(r, pos-1, target, null);
+                if (pos>0)  pred.reduce(r, pos-1, target, null);
                 else {
-                    Input.Region region = child.phase().getLocation().createRegion(target.getLocation());
-                    new Reduction(child, r, r.rewrite(region), target);
+                    Input.Region region = pred.phase().getLocation().createRegion(target.getLocation());
+                    new Reduction(pred, r, r.rewrite(region), target);
                 }
             }
         holder[pos] = old;
@@ -105,11 +105,11 @@ final class Node
         state.invokeEpsilonReductions(phase().token, this);
     }
 
-    // Add/Remove Children/Results //////////////////////////////////////////////////////////////////////////////
+    // Add/Remove Successors/Results //////////////////////////////////////////////////////////////////////////////
 
-    public void removeChild(Result child)   {
-        if (children==null) return;
-        children.remove(child);
+    public void removeSucc(Result succ)   {
+        if (successors==null) return;
+        successors.remove(succ);
         check();
     }
     public void removeResult(Result result) {
@@ -117,14 +117,14 @@ final class Node
         results.remove(result);
         check();
     }
-    public void addChild(Result child)      {
-        if (children==null) return;   // FIXME: this should not happen
-        children.add(child);
+    public void addSucc(Result succ)      {
+        if (successors==null) return;   // FIXME: this should not happen
+        successors.add(succ);
     }
     public void addResult(Result r) {
         if (results.contains(r)) return;
         results.add(r);
-        r.addChild(this);
+        r.addSucc(this);
         if (!fromEmptyReduction) state.invokeReductions(phase().getToken(), this, r);
     }
 
@@ -136,7 +136,7 @@ final class Node
         GraphViz.Node n = gv.createNode(this);
         n.label = "state["+state.toInt()+"]";
         n.shape = "rectangle";
-        boolean hasparents = false;
+        boolean haspreds = false;
         for(Result r : results) n.edge(r, "");
         n.color = state.doomed ? "red" : "green";
         ((GraphViz.Group)phase().toGraphViz(gv)).add(n);