Tutorial by Examples: r

cljs-time gives us option to add/subtract date-times to other date-times. The date times added subtracted should be in form of days, months, years, hours etc. (require '[clj-time.core :as t]) (def example-date (t/date-time 2016 1 1)) ;; #<DateTime 2016-01-01T00:00:00.000Z> ;; Addition ...

List<Integer> immutableEmptyList = List.of(); Initializes an empty, immutable List<Integer>. List<Integer> immutableList = List.of(1, 2, 3, 4, 5); Initializes an immutable List<Integer> with five initial elements. List<Integer> mutableList = new ArrayL...

Set<Integer> immutableEmptySet = Set.of(); Initializes an empty, immutable Set<Integer>. Set<Integer> immutableSet = Set.of(1, 2, 3, 4, 5); Initializes an immutable Set<Integer> with five initial elements. Set<Integer> mutableSet = new HashSet<>(...

Map<Integer, Integer> immutableEmptyMap = Map.of(); Initializes an empty, immutable Map<Integer, Integer>. Map<Integer, Integer> immutableMap = Map.of(1, 2, 3, 4); Initializes an immutable Map<Integer, Integer> with two initial key-value entries. Map<Inte...

Service that is used for communication: import { Injectable } from '@angular/core'; import { Subject } from 'rxjs/Subject'; @Injectable() export class ComponentCommunicationService { private componentChangeSource = new Subject(); private newDateCreationSource = new Subject<Date&...

Factory pattern decouples object creation and allows creation by name using a common interface: class Animal{ public: virtual std::shared_ptr<Animal> clone() const = 0; virtual std::string getname() const = 0; }; class Bear: public Animal{ public: virtual std::shared_ptr...

Node.js is a Javascript engine (Google's V8 engine for Chrome, written in C++) that allows to run Javascript outside the browser. While numerous libraries are available for extending Node's functionalities, the engine comes with a set of core modules implementing basic functionalities. There's curr...

Display Templates can be used to standardize the layout of an object, so let's now see how we can do the same thing for these objects when editing them. Just like display templates, there's two ways to call editor templates for a given type: Html.EditorFor() Html.EditorForModel() Editor templat...

Sometimes you need to create your own Event, one that other plugins can listen to (Vault, among other plugins, does this) and even cancel. Bukkit's Event API allows this to be possible. All you need to do is make a new class, have it extend Event, add the handlers and the attributes your event needs...

#include <mutex> #include <condition_variable> class Semaphore { public: Semaphore (int count_ = 0) : count(count_) { } inline void notify( int tid ) { std::unique_lock<std::mutex> lock(mtx); count++; cout <...

So first we will create rails project and setup device create a rails application rails new devise_example now add devise to gem list you can find a file named 'Gemfile' at the root of rails project Then run bundle install Next, you need to run the generator: rails generate devise:insta...

MultiTrigger is not needed frequently but there are some situations where it is very handy. MultiTrigger behaves similarly to Trigger or DataTrigger but it has multiple conditions. All the conditions must be true for a Setters to fire. Here is a simple example: <!-- Text field needs to be initia...

The following function adds four threads. Three threads compete for the semaphore, which is set to a count of one. A slower thread calls notify_one(), allowing one of the waiting threads to proceed. The result is that s1 immediately starts spinning, causing the Semaphore's usage count to remain be...

Introduction Julia uses the following syntax for dictionaries: Dict({k₁ => v₁, k₂ => v₂, …, kₙ₋₁ => vₙ₋₁, kₙ => vₙ) While Python and JSON looks like this: {k₁: v₁, k₂: v₂, …, kₙ₋₁: vₙ₋₁, kₙ: vₙ} For illustrative purposes we could also use this syntax in Julia and add new seman...

For loops can be really useful in TWIG, allowing the creation of data-dynamic web pages. Say we create a simple array of numbers: {% set array = "3,1,2" %} We can then iterate over the array and print out whatever we want. Any data within the array block will be outputted in relation ...

JavaScript uses reference counting technique to detect unused objects. When reference count to an object is zero, that object will be released by the garbage collector. Weakmap uses weak reference that does not contribute to reference count of an object, therefore it is very useful to solve memory l...

To create our own MessageBox control simply follow the guide below... Open up your instance of Visual Studio (VS 2008/2010/2012/2015/2017) Go to the toolbar at the top and click File -> New Project --> Windows Forms Application --> Give the project a name and then click ok. O...

public FontFamily Maneteke = GetResourceFontFamily(Properties.Resources.manteka);

public static FontFamily GetResourceFontFamily(byte[] fontbytes) { PrivateFontCollection pfc = new PrivateFontCollection(); IntPtr fontMemPointer = Marshal.AllocCoTaskMem(fontbytes.Length); Marshal.Copy(fontbytes, 0, fontMemPointer, fontbytes.Length); pfc.AddMemoryFont(fontMemPo...

Signals can have a default handler. All you need to do is to give it a body when you declare it. public class Emitter : Object { public signal void my_signal () { print ("Hello from the default handler!\n"); } } This handler will always be called after the connected...