RunKit + 
Try any Node.js package right in your browser
This is a playground to test code. It runs a full Node.js environment and already has all of npm’s 1,000,000+ packages pre-installed, including futil-js. Try it out:
var F = require('futil-js')
var cities = ['London', 'Boston', 'Lisbon']
F.dotJoinWith((c) => c.startsWith('L'))(cities)
// "London.Lisbon"
F.arrayToObject(
(c) => c.toLowerCase(),
(c) => c.toUpperCase()
)(cities)
// {boston: "BOSTON", lisbon: "LISBON", london: "LONDON"}
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require()any package directly from npm- use arrow functions, classes, template strings, and most of ES6
awaitany promise instead of using callbacks (example)- create your own embedded node.js snippets
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