checkpoint

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

diff --git a/src/edu/berkeley/sbp/Atom.java b/src/edu/berkeley/sbp/Atom.java
index cb7a379..a5f7e87 100644 (file)
--- a/src/edu/berkeley/sbp/Atom.java
+++ b/src/edu/berkeley/sbp/Atom.java
@@ -13,8 +13,6 @@ public abstract class Atom<T> extends Element implements Topology<T> {
     protected abstract Topology<T> top();
     public    abstract String toString();
 
-    public Topology toAtom() { return this; }
-
     // Topology Thunks //////////////////////////////////////////////////////////////////////////////
 
     public Topology<T>       unwrap()                   { return top().unwrap(); }
@@ -34,7 +32,7 @@ public abstract class Atom<T> extends Element implements Topology<T> {
     public static class Infer<T extends Input> extends Atom<T> {
         private final Element e;
         public Infer(Element e) { this.e = e; }
-        public Topology<T> top() { return (Topology<T>)e.toAtom(); }
+        public Topology<T> top() { return (Topology<T>)toAtom(e); }
         public String toString() { return e.toString(); /* FIXME should be toAtom() */ }
     }
     
@@ -44,5 +42,14 @@ public abstract class Atom<T> extends Element implements Topology<T> {
         public Topology<T> top() { return ((Topology<T>)a.top()).complement(); }
         public String toString() { return "~"+a; }
     }
+
+    static Topology toAtom(Element e) {
+        if (e instanceof Atom) return (Atom)e;
+        if (e instanceof Sequence) return ((Sequence)e).toAtom();
+        Topology ret = null;
+        for(Sequence s : (Union)e)
+            ret = ret==null ? toAtom(s) : ret.union(s.toAtom());
+        return ret;
+    }
 }