JS Examples: Failing to use await with async functions

README.md

A teaching example to show what happens when you don't have an await on an async method invocation.

Without the away, the program will print:

1612325635779 slowMessage start
1612325635781 leaving program
1612325637784 slowMessage end

When adding the await in front of slowMessage, the order is as expected:

1612325724509 slowMessage start
1612325726516 slowMessage end
1612325726516 leaving program

missing-await-example.js

const timeout = (ms) => new Promise(resolve => setTimeout(resolve, ms));
const slowMessage = async () => {
  console.log(`${Date.now()} slowMessage start`);
  await timeout(2000);
  console.log(`${Date.now()} slowMessage end`);
}
(async () => {
  // TODO: The next line needs an await, but see what happens without it
  slowMessage();
  console.log(`${Date.now()} leaving program`);
})()