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Discussion on: A quick guide to JavaScript Promises

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Replies for: Excellent article, I only have one suggestion. Avoid using either .forEach or .reduce for sequential promise execution - at least when overwriting...

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Daniel Levy •

Also, another example of bluebird features, promisify existing callback-based libs using a common method.

So to read a file w/ Promises, use:

const Promise = require('bluebird');
const fs = Promise.promisifyAll(require('fs'));

fs.readFileAsync('/etc/hosts')
.then(content => {
  console.log('File content:', content);
}).catch(err => {
  console.error('An error occurred reading this file.', err.message);
});