06-promises.ts

// Promise<number>
var promisedNumber = new Promise(function (fulfill, reject) {
  setTimeout(() => { fulfill(10) }, 1000)
});

// Promise<string>
var promisedString = new Promise(function (fulfill, reject) {
  setTimeout(() => { fulfill('hello') }, 500)
})

console.log('start')

promisedNumber.then(
  // using arrow functions to "save" some visual space
  (value) => {
    console.log('number: ', value)
    promisedString.then(
      (value) => { console.log('string:', value) },
      (err) => { console.log('error:', err.message) }
    )
  },
  (err) => { console.log('error: ', err.message) }
)

console.log('finish')