adding is alias for contramap

amarpotghan · amarpotghan · commit 68253583b1a1 · 2015-02-09T14:32:48.000+05:30
diff --git a/core/src/main/java/fj/function/Booleans.java b/core/src/main/java/fj/function/Booleans.java
@@ -94,6 +94,16 @@ public static <A, B>  F<B, Boolean> contramap(F<B, A> f, F<A, Boolean> p){
         return compose(p, f);
     }
 
+    /**
+     * alias for contramap
+     * @param p predicate to be mapped over
+     * @param f function
+     * @return predicate function
+     */
+    public static <A, B>  F<B, Boolean> is(F<B, A> f, F<A, Boolean> p){
+        return contramap(f, p);
+    }
+
     /**
      * returns inverse of contramap
      * @param p predicate to be mapped over
