title: What's the purpose of beforeAll() in Jasmine?
body: <p>Why should we not just replace <code>beforeAll(function(){ let foo = 'test' })</code> with <code>let foo = 'test'</code> ?  What's the purpose of <code>beforeAll</code> if the second way is fine?</p>
  
  <p>Here's the official definition by the way: The beforeAll function executes once and only once for the describe block containing it, before any of the beforeEach functions or any of the specs.</p>