Three Optional Chaining Operators in TypeScript

In this tutorial, I will go over the following three optional chaining operators and explain why we might want to use them in our TypeScript or JavaScript code:

  • ?.
  • ?.[]
  • ?.()

#javascript #typescript #webdev 

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Three Optional Chaining Operators in TypeScript
Ray  Patel

Ray Patel

1619565060

Ternary operator in Python?

  1. Ternary Operator in Python

What is a ternary operator: The ternary operator is a conditional expression that means this is a comparison operator and results come on a true or false condition and it is the shortest way to writing an if-else statement. It is a condition in a single line replacing the multiline if-else code.

syntax : condition ? value_if_true : value_if_false

condition: A boolean expression evaluates true or false

value_if_true: a value to be assigned if the expression is evaluated to true.

value_if_false: A value to be assigned if the expression is evaluated to false.

How to use ternary operator in python here are some examples of Python ternary operator if-else.

Brief description of examples we have to take two variables a and b. The value of a is 10 and b is 20. find the minimum number using a ternary operator with one line of code. ( **min = a if a < b else b ) **. if a less than b then print a otherwise print b and second examples are the same as first and the third example is check number is even or odd.

#python #python ternary operator #ternary operator #ternary operator in if-else #ternary operator in python #ternary operator with dict #ternary operator with lambda

Three Optional Chaining Operators in TypeScript

In this tutorial, I will go over the following three optional chaining operators and explain why we might want to use them in our TypeScript or JavaScript code:

  • ?.
  • ?.[]
  • ?.()

#javascript #typescript #webdev 

Sierra  Roob

Sierra Roob

1591237444

Explain: Three dots or spread operator

Explain: Three dots or spread operator
Javascript Three dot is spread operator or syntax
Unbelievable Feature release by ES6. it’s called spread operator or rest operator
Let’s deep dive into all features. ES6 provides many operators and feature but some beginners are failed to remember this feature. From many experience developer also not using this feature during development

#javascript #spread operator #three dot #operator

Abdullah  Kozey

Abdullah Kozey

1617738420

Unformatted input/output operations In C++

In this article, we will discuss the unformatted Input/Output operations In C++. Using objects cin and cout for the input and the output of data of various types is possible because of overloading of operator >> and << to recognize all the basic C++ types. The operator >> is overloaded in the istream class and operator << is overloaded in the ostream class.

The general format for reading data from the keyboard:

cin >> var1 >> var2 >> …. >> var_n;

  • Here, var1var2, ……, varn are the variable names that are declared already.
  • The input data must be separated by white space characters and the data type of user input must be similar to the data types of the variables which are declared in the program.
  • The operator >> reads the data character by character and assigns it to the indicated location.
  • Reading of variables terminates when white space occurs or character type occurs that does not match the destination type.

#c++ #c++ programs #c++-operator overloading #cpp-input-output #cpp-operator #cpp-operator-overloading #operators

Fern  Wisozk

Fern Wisozk

1613792700

Optional Chaining vs Assertion Operator in TypeScript

If you have been using TypeScript, chances are you have come across the weird “?.” & “!” operators while writing code. And if you are like me, then you might have pulled your hair out trying to figure out the difference between them. Well, rest assured because after reading this article, you will have a clear picture of the two operators and the difference between them.

Before we jump to the difference between these two, let us first understand the behavior of these operators.

1. (?.) — Optional Chaining

Before we jump in to understand optional chaining, let’s take a look at this code written in JavaScript.

Image for post

JavaScript Example

In the above code, let’s say we have a data variable but we are not aware of its contents. It may be a null valueundefined, or it may have some properties. To return “data.getName()”, we first have to check whether data is not null and not undefined . Not performing this check may result in an error if the data variable is undefined or null.

Typescript makes writing code like this easy and much simpler to read. With optional chaining, the above code can be re-written in TypeScript as:

Image for post

TypeScript Example

Wasn’t that concise and clean? The star of the show in optional chaining is the "?.” operator that checks if the variable is either null or undefined.

If the "?.” operator finds that the variable is either null or undefined, TypeScript will immediately stop running the expression.

#reactjs #typescript #javascript