added safe versions of minimum and maximum for List

shimib · shimib · commit d353400b4916 · 2017-01-23T08:46:46.000+02:00
diff --git a/core/src/main/java/fj/data/List.java b/core/src/main/java/fj/data/List.java
@@ -1465,6 +1465,16 @@ public final A maximum(final Ord<A> o) {
     return foldLeft1(o::max);
   }
 
+  /**
+   * Returns the maximum element in this list according to the given ordering.
+   *
+   * @param o An ordering for the elements of the list.
+   * @return The optional maximum element in this list according to the given ordering.
+   */
+  public final Option<A> maximumOption(final Ord<A> o) {
+	  return headOption().map(x -> maximum(o));
+  }
+  
   /**
    * Returns the minimum element in this list according to the given ordering.
    *
@@ -1474,6 +1484,16 @@ public final A maximum(final Ord<A> o) {
   public final A minimum(final Ord<A> o) {
     return foldLeft1(o::min);
   }
+  
+  /**
+   * Returns the minimum element in this list according to the given ordering.
+   *
+   * @param o An ordering for the elements of the list.
+   * @return The optional minimum element in this list according to the given ordering.
+   */
+  public final Option<A> minimumOption(final Ord<A> o) {
+	  return headOption().map(x -> minimum(o));
+  }
 
   public final java.util.List<A> toJavaList() {
     return new java.util.LinkedList<>(toCollection());
