await-each

Iterate a list and asynchronously wait for each callback to finish before processing next

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await-each
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Readme

Await Each
Iterate async functions!
awaitEach(values, async function(item) {
  return await doSomething();
}).then(function(responses) {
  console.log(responses);
});

Will wait until each callback is resolved before iterating to the next.
No dependency on async functions!
Can also be used with just promises:
awaitEach(values, function(item) {
  return Promise.resolve(item);
}).then(function(responses) {
  console.log(responses);
});

Mixin with underscore:
_.mixin({awaitEach});

Install

npm install await-each --save

Why?

How is this any different than:
values.forEach(async function(item) {
  await doSomething();
});

In the code above, each callback will wait for it's own await to resolve before continuing, but that wont stop the next callback from starting.
Consider this code:
values.forEach(async function(item) {
  console.log('A');
  await doSomething();
  console.log('B');
});

Because each iteration does not wait for the previous the output would likely be something like:
A A A B B B

Using awaitEach, each iteration waits for the prev to resolve before starting.
So converting the above code to:
awaitEach(values, async function(item) {
  console.log('A');
  await doSomething();
  console.log('B');
});

Will guarantee the output will be:
A B A B A B