p => ({ foo: 'bar' });

p => 10;
p => 'foo';
p => true;
p => [1,2,3];
p => null;
p => /^foo$/;

var func = p => { foo: "bar" }

var func = function (p) {
  foo:
  "bar"; //obviously no return here!
}

p => ({ foo: 'bar' })