JS Built-ins
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ArrayArray.prototype.shiftbeginner

Array.prototype.shift() — shifting an empty array

📖 Usage Example
const arr = []
arr.shift()  // → undefined  (empty array)

shift() returns undefined when called on an empty array — handle this case if needed.

shift() on an empty array

When called on an empty array, shift() returns undefined rather than throwing an error.

([] as number[]).shift() // undefined

This is important to know when writing defensive code.

💡 Hints (2)
  • • `shift()` on an empty array returns `undefined` — it does not throw.
  • • Use a type assertion `([] as number[])` to satisfy TypeScript.