Add array difference and boolean function inversion

Author: przemyslawzalewski

array/difference.js

@@ -0,0 +1,5 @@
+export default (xs, ys) => {
+  const zs = new Set(ys);
+
+  return xs.filter(x => !zs.has(x));
+};

array/index.js

@@ -1,5 +1,6 @@
 import any from "./any.js";
 import are from "./are.js";
+import difference from "./difference.js";
 import differs from "./differs.js";
 import duplicates from "./duplicates.js";
 import empty from "./empty.js";
@@ -40,6 +41,7 @@ import zipWith from "./zipWith.js";
 export {
   any,
   are,
+  difference,
   differs,
   duplicates,
   empty,
@@ -81,6 +83,7 @@ export {
 export default {
   any,
   are,
+  difference,
   differs,
   duplicates,
   empty,

function/index.js

@@ -5,6 +5,7 @@ import memoize from "./memoize.js";
 import memoizeShallow from "./memoizeShallow.js";
 import memoizeWith from "./memoizeWith.js";
 import noOp from "./noOp.js";
+import not from "./not.js";
 import pipe from "./pipe.js";
 import when from "./when.js";
 import whenTrue from "./whenTrue.js";
@@ -17,6 +18,7 @@ export {
   memoizeShallow,
   memoizeWith,
   noOp,
+  not,
   pipe,
   when,
   whenTrue
@@ -30,6 +32,7 @@ export default {
   memoizeShallow,
   memoizeWith,
   noOp,
+  not,
   pipe,
   when,
   whenTrue

function/not.js

@@ -0,0 +1 @@
+export default f => (...args) => !f(...args);