Tutorial by Examples: n

&& has precedence over ||, this means that parentheses are placed to evaluate what would be evaluated together. c++ uses short-circuit evaluation in && and || to not do unnecessary executions. If the left hand side of || returns true the right hand side does not need to be evaluate...

To execute a Redis command using Jedis, you make method calls against the Jedis object you created from the pool. Jedis exposes Redis commands as method calls, some example are: - String get(String key) - Long geoadd(String key, double longitude, double latitude, String member) - List<String...

Many C++ libraries use enums and return/receive data using vectors that contain enums. As C enums are not Objective-C objects, Objective-C collections cannot be used directly with C enums. The example below deals with this by using a combination of an NSArray and generics and a wrapper object for th...

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 ...

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...

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...

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...

If you have a lot of commands, you shouldn't put them all in the main class. Make a new class and have it implement CommandExecutor Add the following to the class: @Override public boolean onCommand(CommandSender sender, Command cmd, String label, String[] args) { } In your...

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...

Installing lxml is very easy, had become an easy jobs since Python 2.7.9 (because it comes with an utility which helps developers to download install dependency in an easy manner like Maven for Java) at first you have to run the command then start coding. pip install lxml The second way is to in...

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...

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...

public static class Res { /// <summary> /// URL: https://www.behance.net/gallery/2846011/Manteka /// </summary> public static FontFamily Maneteke = GetResourceFontFamily(Properties.Resources.manteka); public static FontFamily GetRes...

Signals are only available to GObject classes. They can only be public, which means that any part of the code can connect handlers and trigger them. public class Emitter : Object { // A signal is declared like a method, // but with the signal keyword. public signal void my_signal ();...

You can write detailed signals with the [Signal (detailed = true)] attribute. public class Emitter : Object { [Signal (detailed = true)] public signal void detailed_signal (); public void emit_with_detail (string detail) { this.detailed_signal[detail] (); } } void...

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...