promise each

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showing results for - "promise each"
Addison
23 Jun 2019
1// The array to be iterated over can be a mix of values and promises.
2var fileNames = ["1.txt", Promise.resolve("2.txt"), "3.txt", Promise.delay(3000, "4.txt"), "5.txt"];
3
4Promise.each(fileNames, function(fileName, index, arrayLength) {
5    // The iteration will be performed sequentially, awaiting for any
6    // promises in the process.
7    return fs.readFileAsync(fileName).then(function(fileContents) {
8        // ...
9
10        // The final resolution value of the iterator is is irrelevant,
11        // since the result of the `Promise.each` has nothing to do with
12        // the outputs of the iterator.
13        return "anything"; // Doesn't matter
14    });
15}).then(function(result) {
16    // This will run after the last step is done
17    console.log("Done!")
18    console.log(result); // ["1.txt", "2.txt", "3.txt", "4.txt", "5.txt"]
19});
20