join()

join<T>(array, separator?): string

Converts all elements in array into a string separated by separator.

DEPRECATED

Use array.join(separator) directly instead.

Reason:
Native equivalent method now available

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Type Parameters

T: T

The type of elements in the array.

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Parameters

array: T[]

The array to convert.

separator?: string = ","

The element separator.

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Returns: string

The joined string.

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See Also

• Array.join() - MDN
• Browser support - Can I Use

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Since

2.0.0

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Also known as

join (Lodash, es-toolkit, Remeda, Ramda, Effect) · ❌ (Radashi, Modern Dash, Antfu)

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Example

const numbers = [1, 2, 3, 4, 5];

// ❌ Deprecated approach
const joined = join(numbers, '-');
console.log(joined); // "1-2-3-4-5"

// ✅ Recommended approach
const joinedNative = numbers.join('-');
console.log(joinedNative); // "1-2-3-4-5"

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How it works?

Joins array elements into a string. Deprecated: Use array.join() directly.

Native Equivalent

// ❌ join(arr, '-')
// ✅ arr.join('-')

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Use Cases

Create comma-separated string 📌

Join array elements into a string.

#join#comma#string#list

const tags = ["javascript", "typescript", "nodejs"];
tags.join(", ");
// => "javascript, typescript, nodejs"

Build path from segments

Combine path segments with a separator.

#build#path#segments#URL

const segments = ["home", "user", "documents"];
segments.join("/");
// => "home/user/documents"

Format display list

Create readable lists for display.

#format#display#list#readable

const names = ["Alice", "Bob", "Charlie"];
names.join(" and ");
// => "Alice and Bob and Charlie"