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5 practical TypeScript operators to help you improve your development capabilities!
5 practical TypeScript operators to help you improve your development capabilities!
In this article, I will show you how I improved my skills in TypeScript. I'll introduce you to 5 satisfying operators that will help you better understand TypeScript and how to use it. Here are the operators I will introduce:
Non-Null Assertion Operator
Optional Chaining Operator
Null coalescing operator
Explicit type assertion
Explicit type conversion
1. Non-null assertion operator
The non-null assertion operator is a trailing exclamation mark (!), which tells TypeScript that the value of the expression will not Is null or undefined. This avoids type errors due to possible null or undefined values. [Recommended learning: javascript video tutorial]
Example:
const element: HTMLElement | null = document.getElementById("my-element");
const width: number = element!.offsetWidth;Here, element may be null, but We use the non-null assertion operator to tell TypeScript that we know the value of element is not null, so no type error will occur.
2. Optional Chaining Operator
The optional chaining operator (?.) allows you to access object properties without having to worry about properties does it exist. If the property does not exist, undefined is returned.
Example:
interface Person {
name: string;
address?: {
city: string;
};
}
const person: Person = {
name: "John",
};
const city = person.address?.city;Here, the address attribute is optional, so we use the optional chaining operator to safely access city properties without throwing an error.
3. Null coalescing operator
The empty coalescing operator (??) is a concise way to provide a default value when Used when the value of an expression is null or undefined.
Example:
const value: number | null = null; const defaultValue = 42; const result = value ?? defaultValue;
Here, when value is null, the value of result will be defaultValue.
4. Explicit type assertion
Sometimes, you may want to explicitly assert one type to another type. You can do this using the <Type> syntax or the as Type syntax.
Example:
const input: unknown = "42"; const value: number = <number>(<string>input).length;
Or:
const input: unknown = "42"; const value: number = (input as string).length;
Here, we assert input of type unknown to string, and then assert its length to number.
5. Explicit type conversion
In some cases, you may want to convert a value from one type to another. To do this, you use the type's constructor.
Example:
const value: string = "42"; const numberValue: number = Number(value);
Here we convert string type value to number type numberValue.
Understanding these operators will help you better understand TypeScript and improve your skills. I hope you'll take advantage of these operators to improve your TypeScript programming!
Original link: https://dev.to/codeoz/how-i-improve-my-skills-in-typescript-5-satisfies-operator-2312
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