Head and Tail

Data Structures, Operators & Stringseasy

Course · Section 9: Data Structures, Modern Operators and Strings · Lecture 111: The Spread Operator (...)

Implement `headTail(arr)` returning `{ head, tail }` where `head` is the first element and `tail` is an array of the rest, using array destructuring with a rest element.

Sample tests

Input: headTail([1,2,3])

Output: {"head":1,"tail":[2,3]}

Input: headTail([5])

Output: {"head":5,"tail":[]}

+ 1 hidden test run on Submit.

Hints

Common pitfalls

On an empty array head is undefined; the tests here use non-empty inputs.

Learning resources

MDN: Destructuring assignment

Visualize this concept: Spread and Rest →

Approach & explanation (try first)

Destructuring with a rest element captures the first item and gathers the remainder into a new array.

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