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Setup First, install the necessary packages with: npm install express cors mongoose Code Then, add dependencies to server.js, create the database schema and the name of the collection, create an Express.js server, and connect to MongoDB: var express = require('express'); var cors = require('...

Use $this to refer to the current object. Use self to refer to the current class. In other words, use $this->member for non-static members, use self::$member for static members. In the example below, sayHello() and sayGoodbye() are using self and $this difference can be observed here. cl...

As we know we can declare an array with default values: int[] arr = new int[10]; This will create an array of 10 integers with each element of the array having value 0 (the default value of type int). To create an array initialized with a non-default value, we can use Enumerable.Repeat from the...

You might have heard that everything in Python is an object, even literals. This means, for example, 7 is an object as well, which means it has attributes. For example, one of these attributes is the bit_length. It returns the amount of bits needed to represent the value it is called upon. x = 7 ...

<svg width="800px" height="600px"> <defs> <filter id="inner-glow"> <feFlood flood-color="red"/> <feComposite in2="SourceAlpha" operator="out"/> <feGaussianBlur stdDeviation="2" r...

OVERVIEW cocos2d-x is an open source, cross-platform game engine. It allows developers to code in C++, Lua and Javascript deployment into iOS, Android, Windows Phone, Mac OS X, Windows Desktop and Linux. PREREQUISITES Build Requirements Mac OS X 10.7+, Xcode 4.6+ Windows 7+, VS 2012+ Ubunt...

Since Java 7 it has been possible to use one or more underscores (_) for separating groups of digits in a primitive number literal to improve their readability. For instance, these two declarations are equivalent: Java SE 7 int i1 = 123456; int i2 = 123_456; System.out.println(i1 == i2); // tru...

A common problem when working with Unity is when 2 or more developers are modifying a Unity scene or prefab (*.unity files). Git does not know how to merge them correctly out of the box. Thankfully the Unity team deployed a tool called SmartMerge which makes simple merge automatic. The first thing...

/*(8)*/ SELECT /*9*/ DISTINCT /*11*/ TOP /*(1)*/ FROM /*(3)*/ JOIN /*(2)*/ ON /*(4)*/ WHERE /*(5)*/ GROUP BY /*(6)*/ WITH {CUBE | ROLLUP} /*(7)*/ HAVING /*(10)*/ ORDER BY /*(11)*/ LIMIT The order in which a query is processed and description of each section. V...

HTML and Form Builder is not a core component since Laravel 5, so we need to install it separately: composer require laravelcollective/html "~5.0" Finally in config/app.php we need to register the service provider, and the facades aliases like this: 'providers' => [ // ... ...

Elasticsearch is accessed through a HTTP REST API, typically using the cURL library. The messages between the search server and the client (your or your application) are sent in the form of JSON strings. By default, Elasticsearch runs on port 9200. In the examples below, ?pretty is added to tell El...

Assuming you have a Twilio account and API credentials, add the following to your Gemfile: gem 'twilio-ruby' Alternatively you can gem install twilio-ruby. To have Twilio send an incoming SMS to a particular route in your application, you need to configure the Messaging URL for your phone numbe...

// Get the current colors of the gradient. let oldColors = self.gradientLayer.colors // Define the new colors for the gradient. let newColors = [UIColor.red.cgColor, UIColor.yellow.cgColor] // Set the new colors of the gradient. self.gradientLayer.colors = newColors // Initia...

? This gives you an introduction and overview of IPython's features. object? This lists all methods and fields of the object and its documentation (if it exists). object?? Same as above, provides even more detail about the object, in particular will try to find and display the source cod...

Padding Remember, members of a struct are usually padded to ensure they are aligned on their natural boundary: struct t { int a, b, c, d; // a is at offset 0, b at 4, c at 8, d at 0ch char e; // e is at 10h short f; // f is at 12h (naturally aligned) lo...

Python will implicitly convert any object to a Boolean value for testing, so use it wherever possible. # Good examples, using implicit truth testing if attr: # do something if not attr: # do something # Bad examples, using specific types if attr == 1: # do something if att...

Web applications often require static files like CSS or JavaScript files. To use static files in a Flask application, create a folder called static in your package or next to your module and it will be available at /static on the application. An example project structure for using templates is as f...

open(my $fh, '<', "/some/path") or die $!; my @ary = <$fh>; When evaluated in list context, the diamond operator returns a list consisting of all the lines in the file (in this case, assigning the result to an array supplies list context). The line terminator is retained, and ...

XE2 program CrossPlatformHelloWorld; uses FMX.Dialogs; {$R *.res} begin ShowMessage('Hello world!'); end. Most of the Delphi supported platforms (Win32/Win64/OSX32/Android32/iOS32/iOS64) also support a console so the WriteLn example fits them well. For the platforms that require...

Switching into Protected Mode is easy: you just need to set a single bit in a Control Register. But staying in Protected Mode, without the CPU throwing up its hands and resetting itself due to not knowing what to do next, takes a lot of preparation. In short, the steps required are as follows: ...