Another update from ingydotnet^djgoku

Task/Permutations/JavaScript/permutations-2.js

@@ -0,0 +1,30 @@
+(function () {
+
+  // [a] -> [[a]]
+  function permutations(xs) {
+    return xs.length ? (
+               chain( xs,                            function (x)  {
+        return chain( permutations(deleted(x, xs)),  function (ys) {
+
+        return ( [[x].concat(ys)] );
+
+    })})) : [[]]
+  }
+
+  // monadic bind/chain for lists
+  function chain(xs, f) {
+    return [].concat.apply([], xs.map(f));
+  }
+
+  // drops first instance found
+  function deleted(x, xs) {
+    return xs.length ? (
+      x === xs[0] ? xs.slice(1) : [xs[0]].concat(
+        deleted(x, xs.slice(1))
+      )
+    ) : [];
+  }
+
+  return permutations(['Aardvarks', 'eat', 'ants'])
+
+})();

Task/Permutations/JavaScript/permutations-3.js

@@ -0,0 +1 @@
+[["Aardvarks", "eat", "ants"], ["Aardvarks", "ants", "eat"], ["eat", "Aardvarks", "ants"], ["eat", "ants", "Aardvarks"], ["ants", "Aardvarks", "eat"], ["ants", "eat", "Aardvarks"]]