const demoFunction: (input: boolean) => Promise<string> = (input: boolean) => {
  if (input) {
    return Promise.resolve('hello world');
  } else {
    return Promise.reject('input was false');
  }
}

// Call 1
demoFunction(true).then(() => {
  console.log('Entered then');
}).catch(() => {
  console.log('Entered catch');
});

// Call 2
demoFunction(true).then(() => {
  console.log('Entered then');
}).catch(() => {
  console.log('Entered catch');
}).finally(() => {
  console.log('Entered finally');
});