Andrew  Mata

Andrew Mata

1619407957

Override and NoImplicitOverride for TypeScript Class Inheritance

In this lesson we look at an exciting new feature in TypeScript 4.3. 6 years in the making its finally landed. TypeScript supports the override modifier and even added a new compiler flag for enforcing reliable class inheritance!

Subscribe: https://www.youtube.com/c/BasaratAli/featured

#typescript #javascript

What is GEEK

Buddha Community

Override and NoImplicitOverride for TypeScript Class Inheritance

Yashi Tyagi

1617449307

CA Classes - Best CA Classes Online

Chartered Accountancy course requires mental focus & discipline, coaching for CA Foundation, CA Inter and CA Finals are omnipresent, and some of the best faculty’s classes have moved online, in this blog, we are going to give the best way to find online videos lectures, various online websites provide the CA lectures, Smartnstudy one of the best site to CA preparation, here all faculty’s video lecture available.

check here : ca classes

#ca classes online #ca classes in delhi #ca classes app #ca pendrive classes #ca google drive classes #best ca classes online

Fredy  Larson

Fredy Larson

1599541620

Why the Instance Variable of the Super Class Is Not Overridden in the Sub Class

When we create a variable in both parent and child classes with the same name and try to access it using a parent’s class reference, which is holding a child class’s object, then what do we get?

In order to understand this, let us consider the example below where we declare a variable x with the same name in both Parent and Child classes.

class Parent {
// Declaring instance variable by name `x`
    String x = "Parent`s Instance Variable";
public void print() {
        System.out.println(x);
}
}

class Child extends Parent {

    // Hiding Parent class's variable `x` by defining a variable in child class with same name.
String x = "Child`s Instance Variable";
    @Override
public void print() {
        System.out.print(x);
    // If we still want to access variable from super class, we do that by using `super.x`
        System.out.print(", " + super.x + "\n");
}
}
```

And now, if we try to access `x` using below code, `System.out.println(parent.x)` will print:

```
Parent parent = new Child();

System.out.println(parent.x) // Output – Parent`s Instance Variable


Well generally, we say that the `Child` class will override the variable declared in the `Parent` class, and `parent.x` will give us whatever the `Child`'s object is holding. Because it is the same thing, it happens while we do the same kind of operation on methods.

But, actually, it is not, and the `parent.x` will give us the value of the Parent`s Instance Variable, which is declared in the `Parent` class — but why?

This is because variables in Java do not follow polymorphism and overriding is only applicable to methods, not variables. And when an instance variable in a `child` class has the same name as an instance variable in a `parent` class, then the instance variable is chosen from the reference type.

In Java, when we define a variable in a `Child` class with a name that we have already used to define a variable in the `Parent` class, the Child class's variable hides the parent's variable, even if their types are different. And this concept is known as **variable hiding**.

In other words, when the `child` and `parent` class both have a variable with the same name, the `Child` class's variable hides the `Parent` class's variable. You can read more on variable hiding in the article: [What is Variable Shadowing and Hiding in Java](https://programmingmitra.com/2018/02/what-is-variable-shadowing-and-hiding.html).

#java #tutorial #overriding #method overriding #variable hiding #sub class #super class

Types of Inheritance in Python | Python Inheritance [With Example] | upGrad blog

Introduction

The struggle for a clean code is a battle joined by all the programmers. And that battle can be conquered with a proper armour of object-oriented programming concepts. And proper utilization of OOP concepts helps us to improve code reusability, readability, optimal time and space complexity.

Coding in Python is super fun. It has a whopping number of library support, object-oriented, GUI programmability makes it a hot cake among all the programming languages.

Inheritance is one of the most utilized object-oriented features and implementing it in python is an enthusiastic task. So, let’s start now!

First things first let’s understand the definition of inheritance.

#data science #inheritance #inheritance in python #python #types of inheritance #types of inheritance in python

Andrew  Mata

Andrew Mata

1619407957

Override and NoImplicitOverride for TypeScript Class Inheritance

In this lesson we look at an exciting new feature in TypeScript 4.3. 6 years in the making its finally landed. TypeScript supports the override modifier and even added a new compiler flag for enforcing reliable class inheritance!

Subscribe: https://www.youtube.com/c/BasaratAli/featured

#typescript #javascript

Murray  Beatty

Murray Beatty

1595774760

Overriding Inheritance in New Types Using Omit and Keyof in Typescript

TypeScript can be weird and not very intuitive. Pardon me, I started learning TypeScript in January 2020. And JavaScript programming since 2018, almost two years. Not the little scripts we write in with libraries like JQuery and in small files to manipulate HTML pages but JavaScript as a full fledged programming language to build libraries and code off any framework/library written in JavaScript. For everyone abreast of developments in the JavaScript world, learning TypeScript is imperative. Deno the new JavaScript and TypeScript runtime has first class support for TypeScript.

What is helping me in learning TypeScript is my knowledge of Java. Java is statically typed and that’s what TypeScript is out to achieve for JavaScript. Compile time type checking. Types and Interfaces are used to derive objects that conform to specific types. As we all know TypeScript is a turing complete programming language.

The Famous Type

Let’s cut to the chase. Here we go:

type ModelFields<T> = Partial<Omit<T, keyof BaseModel>> & {
   created_at?: Date;
   updated_at?: Date;
};

For an intermediate or expert TypeScript programmer. This ModelFieldstype is simple.

It means, Pick the properties of generic type T and exclude all properties of BaseModel and use the intersection type and include created_at and updated_at and we have a brand new type.

#typescript #javascript #inheritance #stackoverflow #programming