Rest Parameters

Rest parameters allow a function to accept an indefinite number of arguments as an array.

Syntax

TYPESCRIPT

1
2
3

function sum(...numbers: number[]): number {
    return numbers.reduce((a, b) => a + b, 0);
}

Rest Parameters

TYPESCRIPT

1
2
3
4
5
6
7
8
9
10

function sum(...numbers: number[]): number {
    return numbers.reduce((a, b) => a + b, 0);
}

function log(level: string, ...messages: string[]): void {
    console.log(`[${level}]`, ...messages);
}

console.log(sum(1, 2, 3, 4, 5));
log("INFO", "Server started", "on port 3000");

Try It Yourself

Practice

1

Exercise

Practice this concept.

Answer

Write the code as shown above.

Quick Quiz

1

What did you learn?

Concept A

Concept B

Concept C

Concept D

This covers the basics.

Retry Quiz

Interview Questions

Explain this concept.

It is a fundamental TypeScript feature.

Previous

Optional & Default Parameters

Tutorial Complete

Back to TypeScript