SEARCH KEYWORD -- Inheritance



  Mutli-inheritance bug between python 2.7 and 3.7

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: 2019/05/16 class A: def getVal(self): print("cal...

   PYTHON,PYTHON 3,INHERITANCE     2019-05-16 08:33:52

  Three ways to define class in JavaScript

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...

   JavaScript,Class,Method,Private,Inheritance     2012-07-09 11:59:51

  Should we use Abstract class or Interface?

When we write programs, we may often get into a situation where we don't know whether we should use Abstract class or Interface when we want to define an abstract object. These two are very similar and they are interchangeable in many cases. On Stackoverflow, this question is asked lots of times and it's related to many programming languages. Also in the official documentation of PHP regarding the Abstract class and Interface, people are arguing about this. To understand this question, their dif...

   DIFFERENCE,INTERFACE,ABSTRACT CLASS,COMPARISON,OOP     2013-04-15 11:44:36

  C++, Ruby and CoffeeScript complexity comparison

There are many programming languages around the world, they all designed to help programmer solve some problems, finish some tasks. These languages are often divided into different types, there are structural, object-oriented, functional, scripting languages etc. Some are easy to pick up such as Java, while some are thought to be difficult to learn such as C++. So how do we understand complexities of different programming languages?Many people agree that C++ is very complex languages, it has poi...

   Complexity, languages, C++,Ruby,CoffeeScript     2012-06-12 04:46:01

  Understand JavaScript prototype

For an front end programming language like JavaScript, if we want to understand its OOP feature, we need to understand its objects, prototype chain, execution context, closure and this keyword in deep. If you have a good understanding on these concepts, you should be confident that you can handle this language well. The inheritance in JavaScript is not class inheritance like Java, but it adopts another mechanism-- prototype inheritance. The key to prototype inheritance is the prototype chain mec...

   JavaScript, prototype, __proto__     2013-02-02 02:34:09

  jsonSerialize() in extended class

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: <?php class ArrayValue implements JsonSerializable { public function __construct(array $array) { $this->array = $array; ...

   JSON,jsonSerialize,Inheritance,extends     2014-07-26 05:54:00

  Must read C++ book list

Every programmer should read some books to enhance their understanding about the language before the start to practice. But some of us often wonder what books we should read and in what order. Some books may not be suitable for beginners and some books may cover the similar topics. Here I summarize a C++ book list we should read.Stage 1"Essential C++" : It is short but powerful and it can enhance our understanding of C++'s features.This book is specifically designed to bring you up to speed in a...

   C++,Book list,Read,Effective C++     2012-05-23 13:03:30

  Let 's write some front end codes

I've seen a lot of arguments that there is no much technical value writing web portal, I think that the vast majority of good programmers will try many different things. The low level development and machine learning are not the only technologies which are  full of wisdom and challenges, I wrote web site for a few years, it is difficult to say that this is my initial interest, although I touched on other technologies as well, I still feel building website is challenging. Front end developme...

   Front end development, JavaScript,CSS     2013-01-22 04:00:24

  Disgusting programming language list

To avoid arguments among different programming languages, this ranking only covers the opinions from programmers with multi-language experience. Also it doesn't mean the language is not good if the language is on the list, it just means those developers don't like some features of the language. Below ranking is summarized from Quora、Stack Overflow and Hacker News. 10. Python Reason : It uses code indent to define block level scope, why not use curly braces? It also uses massive colons and ...

   Programming language rank     2013-09-27 09:53:39

  Can a === 1 && a === 2 && a === 3 be true in JavaScript?

Lots of you may be aware that there is famous interview question which asks whether a == 1 && a == 2 && a == 3 can be true in JavaScript. And the answer to this question is YES. The reason is that == will do a non-strict comparison which will evaluate a to a number and this provides the possibility of dynamically return the value when every time a is accessed. Have you ever wondered whether a === 1 && a === 2 && a === 3 can be true? At first glance, it seems this ...

   JAVASCRIPT,===,STRICT COMPARISON     2018-04-06 12:17:29