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COMPUTE answer = 3*var-1 That is a reference to the variable var-1, and not var - 1. COMPUTE answer = 3 * var - 1 Recommended, opinion.

Luminus is a Clojure micro-framework based on a set of lightweight libraries. It aims to provide a robust, scalable, and easy to use platform. With Luminus you can focus on developing your app the way you want without any distractions. It also has very good documentation that covers some of the majo...

Scenario: You need to select an implementation of address validation when a sales order is submitted, and the validator is determined by the country to which the order is shipping. The factory needs to inspect some value passed as an argument to select the correct implementation. First, write an in...

Scenario: You need to resolve a dependency when a method is called, not in the constructor. Solution: Inject an abstract factory into the constructor. When the method is called, it requests the dependency from the abstract factory, which in turn resolves it from the container. (Your class depends o...

const Promise = require('bluebird'), fs = require('fs') Promise.promisifyAll(fs) // now you can use promise based methods on 'fs' with the Async suffix fs.readFileAsync('file.txt').then(contents => { console.log(contents) }).catch(err => { console.error('error reading', er...

Example of map: Promise.resolve([ 1, 2, 3 ]).map(el => { return Promise.resolve(el * el) // return some async operation in real world }) Example of filter: Promise.resolve([ 1, 2, 3 ]).filter(el => { return Promise.resolve(el % 2 === 0) // return some async operation in real world...

const promiseReturningFunction = Promise.coroutine(function* (file) { const data = yield fs.readFileAsync(file) // this returns a Promise and resolves to the file contents return data.toString().toUpperCase() }) promiseReturningFunction('file.txt').then(console.log)

function somethingThatReturnsADisposableResource() { return getSomeResourceAsync(...).disposer(resource => { resource.dispose() }) } Promise.using(somethingThatReturnsADisposableResource(), resource => { // use the resource here, the disposer will automatically close it when ...

const Koa = require('koa') const app = new Koa() app.use(async ctx => { ctx.body = 'Hello World' }) app.listen(8080)

app.use(async (ctx, next) => { try { await next() // attempt to invoke the next middleware downstream } catch (err) { handleError(err, ctx) // define your own error handling function } })

describe('Suite Name', function() { describe('#method()', function() { it('should run without an error', function() { expect([ 1, 2, 3 ].length).to.be.equal(3) }) }) })

var expect = require("chai").expect; describe('Suite Name', function() { describe('#method()', function() { it('should run without an error', function(done) { testSomething(err => { expect(err).to.not.be.equal(null) done() }) }) }) }) ...

describe('Suite Name', function() { describe('#method()', function() { it('should run without an error', function() { return doSomething().then(result => { expect(result).to.be.equal('hello world') }) }) }) })

Unlike var, const/let are bound to lexical scope rather than function scope. { var x = 1 // will escape the scope let y = 2 // bound to lexical scope const z = 3 // bound to lexical scope, constant } console.log(x) // 1 console.log(y) // ReferenceError: y is not defined console.log(z...

Arrow functions automatically bind to the 'this' lexical scope of the surrounding code. performSomething(result => { this.someVariable = result }) vs performSomething(function(result) { this.someVariable = result }.bind(this))

Before starting work with scrapy you have to start a project where you want to store your code. Enter the directory and run this code scrapy startproject helloProject The third part of this code is project name. This code will create a "helloProject" directory with the following conten...

You can qualify a whole folder folder for a specific device type, its files will override the ones outside it on that device: / DeviceFamily-Mobile PageOfEden.xaml MainPage.xaml MainPage.xaml MainPage.xaml.cs PageOfEden.xaml PageOfEden.xaml.cs Files inside the qualifying folder won...

Multidimensional arrays follow the same rules as single-dimensional arrays when passing them to a function. However the combination of decay-to-pointer, operator precedence, and the two different ways to declare a multidimensional array (array of arrays vs array of pointers) may make the declaratio...

This ability was added to the Bind markup extension after v1607 (Redstone 1). You can specify a function path, as well as arg paths and constant args. Let's assume we have a function defined in our backcode: public string Translate(string text, string from, string to) Now we can use bind to eva...

This guide assumes you have already installed react, redux, react-router and react-redux and have configured react, redux and react-router., If you haven't, Please do so. Note: While react-router in not a dependency of react-redux, It's very likely that we will using it in our react application for...