Hard memo memory reduction (#258)

clinuxrulz · jbgi · commit 97b767e89e6d · 2016-05-26T15:29:11.000+02:00
* hard memo memory reduction.

Dereferences the computation allowing it to become garbage collected
once the value has been memorised.

* removed initialized
diff --git a/core/src/main/java/fj/P1.java b/core/src/main/java/fj/P1.java
@@ -268,19 +268,18 @@ public static <A> P1<A> memo(F0<A> f) {
 	}
 
     static class Memo<A> extends P1<A> {
-      private final P1<A> self;
-      private volatile boolean initialized;
+      private volatile P1<A> self;
       private A value;
 
       Memo(P1<A> self) { this.self = self; }
 
       @Override public final A _1() {
-        if (!initialized) {
+        if (self != null) {
           synchronized (this) {
-            if (!initialized) {
+            if (self != null) {
               A a = self._1();
               value = a;
-              initialized = true;
+              self = null;
               return a;
             }
           }
