I'm going through promise-it-wont-hurt course on http://nodeschool.io/ . Below is the solution of assignment promise_after_promise
'use strict';
/* global first, second */
var firstPromise = first();
var secondPromise = firstPromise.then(function (val) {
return second(val);
});
secondPromise.then(console.log);
// As an alternative to the code above, ou could also do this:
// first().then(second).then(console.log);
they are not passing any value to console.log but it still print the value how?
promise.then
takes a function (two actually, but only one is used here). Then it calls this function with the result of the resolved promise. In this case, console.log
is a function, which is called with the result of the resolved promise.
The easier-to-understand alternative would have been
secondPromise.then(function(result) {
console.log(result);
});
But it creates an unnecessary function.
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