repeat()

When working with JavaScript, you may encounter situations where you need to repeat a string a specific number of times.

Whether you’re generating repeated patterns or simply duplicating text, the repeat() method provides a simple and effective way to achieve this.

The repeat() method is a built-in function in JavaScript that allows you to repeat a string a specified number of times. Here is the basic syntax:

string.repeat(count);

string is the string that you want to repeat, and count is the number of times you want the string to be repeated. Here’s an example:

let word = "Hello!";
let repeatedWord = word.repeat(3);
console.log(repeatedWord);  // Output: "Hello!Hello!Hello!"

In this case, the string Hello! is repeated three times, resulting in Hello!Hello!Hello!.

While the repeat() method is useful, there are a few exceptions and limitations to keep in mind.

The count parameter must be a non-negative number. If you pass a negative number, JavaScript will throw a RangeError.

let word = "Test";
console.log(word.repeat(-1));  // Throws RangeError: Invalid count value

The count must be a finite number. If you try to repeat a string an infinite number of times or use Infinity as the count, you will also get a RangeError.

In JavaScript, Infinity is a special value that represents an infinite quantity. It’s used to denote numbers that are larger than any finite number.

let word = "Test";
console.log(word.repeat(Infinity));  // Throws RangeError: Invalid count value

If the count is not an integer (such as a decimal like 2.5), the repeat() method will round it down to the nearest integer.

let word = "Test";
console.log(word.repeat(2.5));  // Output: "TestTest"

If you pass 0 as the count, the repeat() method will return an empty string.

let word = "Test";
console.log(word.repeat(0));  // Output: ""

The repeat() method can simplify tasks that involve string duplication, making your code more concise and readable.

Whether you’re generating repeated text patterns or filling a space with characters, repeat() can save you from writing loops or more complex code.