Tutorial by Examples: a

Configure babel

Create a file .babelrc in the root of our working directory Filename: .babelrc { "presets": ["es2015","react"] }

React • Setting Up React Environment

HTML file to use react component

Setup a simple html file in the root of the project directory Filename: index.html <!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title></title> </head> <body> <div id="App"></div> ...

React • Setting Up React Environment

Transpile and bundle your component

Using webpack, you can bundle your component: $ webpack This will create our output file in build directory. Open the HTML page in a browser to see component in action

React • Setting Up React Environment

Convert the interface of a class into another interface clients expect. Adapter (or Wrapper) lets classes work together that couldn't otherwise because of incompatible interfaces. Adapter pattern's motivation is that we can reuse existing software if we can modify the interface. Adapter pattern...

C++ • Design pattern implementation in C++

Using gen_server behavior

A gen_server is a specific finite state machine working like a server. gen_server can handle different type of event: synchronous request with handle_call asynchronous request with handle_cast other message (not defined in OTP specification) with handle_info Synchronous and asynchronous mess...

Erlang Language • gen_server behavior

Simple Key/Value Database

This source code create a simple key/value store service based on map Erlang datastructure. Firstly, we need to define all information concerning our gen_server: -module(cache). -behaviour(gen_server). % our API -export([start_link/0]). -export([get/1, put/2, state/0, delete/1, stop/0]). %...

Erlang Language • gen_server behavior

Memory leaks in Java

In the Garbage collection example, we implied that Java solves the problem of memory leaks. This is not actually true. A Java program can leak memory, though the causes of the leaks are rather different. Reachable objects can leak Consider the following naive stack implementation. public class ...

Java Language • Java Memory Management

How to allow reading specific item from group, but prevent listing group members

It is common practice to create groups of items by creating simple value nodes with item ID as key. For example, we can add a user to the group "administrators" by creating a node at /administrators/$user_id with a value true. We don't want anyone to know who administrators are, for securi...

firebase • Database Rules

Installation or Setup

Detailed instructions on getting mono set up or installed.

mono • Getting started with mono

Client side csv download using Blob

function downloadCsv() { var blob = new Blob([csvString]); if (window.navigator.msSaveOrOpenBlob){ window.navigator.msSaveBlob(blob, "filename.csv"); } else { var a = window.document.createElement("a"); a.href = window.URL.createObjectURL(blob, { ...

JavaScript • File API, Blobs and FileReaders

Pointer Operations

There are two operators for pointers: Address-of operator (&): Returns the memory address of its operand. Contents-of (Dereference) operator(*): Returns the value of the variable located at the address specified by its operator. int var = 20; int *ptr; ptr = &var; cout << var &...

C++ • Pointers

Phaser environment setup (Asp.Net MVC5 - Typescript - Visual Studio 2015)

Create a new ASP.Net Project: Select the empty template: Add two new folders: App and Scripts in the root folder: Add npm configuration file in the root folder: { "version": "1.0.0", "name": "phaser.js.environment.setup", "priva...

phaser-framework • Working with TypeScript

If operator

9.0 If(condition > value, "True", "False") We can use the If operator instead of If...Then...Else..End If statement blocks. Consider the following example: If 10 > 9 Then MsgBox("True") Else MsgBox("False") End If is the same as M...

Visual Basic .NET Language • Conditions

Linked List implementation in C++

Creating a List Node class listNode { public: int data; listNode *next; listNode(int val):data(val),next(NULL){} }; Creating List class class List { public: listNode *head; List():head(NULL){} void insertAtBegin(int val); void insertAtEnd(int val)...

C++ • Data Structures in C++

Managing Security

Security was a part of the dark side of the symfony documentation, it has a dedicated component named Security Component. This component is configured in the security.yml file of the main application project. The default configuration is like this one : # app/config/security.yml security: p...

symfony2 • Managing the Symfony firewalls and security

A - Getting Started

In a nutshell, Our Custom Element Should Have a Built in Search Functionality, that searches and marks places on the map. Accept An attribute called location-array , which is a list of places Have a Listener , for listening to an event called “google-map-ready“.This event is fired, when the ele...