When we have run a py3.7 code under py2.x or a py2.x code under 3.x ,if a class do mutli-inheritance from 2 parent and the 2 parents also got inheritance from same parent, the different way to handle inheritance chain between python 2 and 3 will cause some running time bug:Assume we got this sample program inheritTest.py :# Purpose: Test mutli-inheritance different between python2 and 3# Author: Yuancheng Liu# Created: 2019/05/16class A: def getVal(self): print("call A's getVal()") def setVal(self): print("call A's setVal()")class B(A): def getVal(self): ...

Since PHP 5.4.0, there is a convenient interface JsonSerializable which can be used to indicate that a PHP object can be serialized to JSON object. It has only one method which should be implemented by any class which implements this interface. The method is named jsonSerialize().It's really easy to serialize an object to JSON object. Here is one example:<?phpclass ArrayValue implements JsonSerializable { public function __construct(array $array) { $this->array = $array; } public function jsonSerialize() { return $this->array; }}$array = [1, 2, 3];echo json_e...

In object oriented programming, class is the template of object, it defines the properties and methods of a group of objects. Unfortunately, JavaScript doesn't support class, but we can have some workarounds to simulate class.1. Constructor functionThis is the classical approach, it is also the approach mentioned in many text books. It uses the constructor function to simulate class and it uses the keyword this to represent the object internally.function Cat() {　　this.name = "Kelly";}when creating the instance, use the new keyword.var cat1=new Cat();alert(cat1.name); //KellyThe p...

Forget everything you know about object-oriented programming. Instead, I want you to think about race cars. Yes – race cars. Recently I was watching the 24 Hours of Le Mans –a popular racing event in France. The fastest cars in the race are the Le Mans Prototypes. Although these cars are built by car manufacturers like Audi and Peugeot, they are not cars you’ll see on the streets and highways of your home town. They are built exclusively for high-speed endurance racing.Manufacturers put an enormous amount of money into researching, engineering, and building these prot...