2 files changed, 13 insertions, 9 deletions

diff --git a/src/ch/epfl/maze/physical/World.java b/src/ch/epfl/maze/physical/World.java
index 257fa65..9f4f155 100644
--- a/src/ch/epfl/maze/physical/World.java
+++ b/src/ch/epfl/maze/physical/World.java
@@ -7,6 +7,7 @@ import java.util.ArrayList;
 import java.util.EnumSet;
 import java.util.List;
 import java.util.Set;
+import java.util.stream.Collectors;
 
 /**
  * World that is represented by a labyrinth of tiles in which an {@code Animal}
@@ -136,13 +137,12 @@ public abstract class World {
      * @return A set of all available choices at a position
      */
     public final Set<Direction> getChoiceSet(Vector2D position) {
-        Set<Direction> choices = EnumSet.noneOf(Direction.class);
+        Set<Direction> freeDirections = Direction.MOVING_DIRECTIONS
+                .stream()
+                .filter(dir -> this.isFree(position.addDirectionTo(dir)))
+                .collect(Collectors.toSet());
 
-        for (Direction dir : Direction.POSSIBLE_DIRECTIONS)
-            if (this.isFree(position.addDirectionTo(dir)))
-                choices.add(dir);
-
-        return choices.isEmpty() ? EnumSet.of(Direction.NONE) : choices;
+        return freeDirections.isEmpty() ? EnumSet.of(Direction.NONE) : freeDirections;
     }
 
     /**
diff --git a/src/ch/epfl/maze/util/Direction.java b/src/ch/epfl/maze/util/Direction.java
index ac172cb..b3f2e9c 100644
--- a/src/ch/epfl/maze/util/Direction.java
+++ b/src/ch/epfl/maze/util/Direction.java
@@ -1,5 +1,9 @@
 package ch.epfl.maze.util;
 
+import java.util.Collections;
+import java.util.EnumSet;
+import java.util.Set;
+
 /**
  * Directions that an animal can take to move. They represent the four cardinal
  * points ({@code DOWN, UP, RIGHT, LEFT}) from the frame of reference of the
@@ -12,14 +16,14 @@ public enum Direction {
     DOWN, UP, RIGHT, LEFT, NONE;
 
     /**
-     * An array of all the possible directions that can be taken.
+     * A set of all the possible directions that can be taken.
      */
-    public static final Direction[] POSSIBLE_DIRECTIONS = new Direction[]{
+    public static final Set<Direction> MOVING_DIRECTIONS = Collections.unmodifiableSet(EnumSet.of(
             Direction.DOWN,
             Direction.UP,
             Direction.RIGHT,
             Direction.LEFT
-    };
+    ));
 
     /**
      * Returns the integer value of the direction