replace-in-object

Replaces values in objects in a type safe and immutable way.

(Type safety only for TypeScript developers)

const deepObject = {
  foo: {
    bar: {
      hello: "there",
    },
    array: [
      "how",
      "abou",
      "this",
    ],
  },
  cool: "stuff",
};

const replaced = replace(deepObject)
  .foo.bar.hello.with("world")
  .foo.array[1].with("about")
  .foo.array.push("?")
  .done();

const typingExample: {
  [key: string]: string;
} = {
  "hello": "world",
};

// this shorthand is neat when you want to replace a single value (but it works in all cases)
const added = replace(typingExample).newkey.with("This works too")();
const smart = replace(typingExample).hello.update(s => s.toUpperCase())();

const partial = {
  some: {
    thing: "needs",
    to: "change",
  },
};
const merged = replace(partial).some.mergeWith({ to: "new!" })();

expect(replaced.foo.array).toStrictEqual(["how", "about", "this", "?"]);
expect(replaced.foo.bar.hello).toBe("world");
expect(added.newkey).toBe("This works too");
expect(smart.hello).toBe("WORLD");
expect(merged.some.to).toBe("new!");