How to use Readonly Array In Javascript
In TypeScript, you can declare the return type of a generic arrow function to be a readonly array to ensure immutability and prevent unintended modifications to the returned array. This approach enhances code safety and maintains consistency in your application.
Example:
const generateSequence = (): ReadonlyArray<number> => {
const sequence: number[] = [];
for (let i = 1; i <= 5; i++) {
sequence.push(i);
}
return sequence;
};
const result: ReadonlyArray<number> = generateSequence();
console.log(result); // Output: [1, 2, 3, 4, 5]
Output:
[1, 2, 3, 4, 5]
How to Declare the Return Type of a Generic Arrow Function to be an Array ?
In TypeScript, declaring the return type of a generic arrow function to be an array is generally essential when we want to ensure that the function always returns the array of a particular type. This is especially necessary for maintaining type safety and maintaining consistency in our code. Declaring the return type as an array, one can avoid unintentional errors and make code more easy to understand. There are several methods to declare the return type of a generic arrow function to be an array which are as follows: