first()
first<
T>(array):T|undefined
Gets the first element of array.
DEPRECATED
Use array[0] or array.at(0) directly instead.
Reason:
Native equivalent method now available
Type Parameters
T: T
The type of elements in the array.
Parameters
array: T[]
The array to query.
Returns: T | undefined
The first element of the array, or undefined if empty.
See Also
Since
2.0.0
Also known as
at(arr, 0) (Antfu) · first (Lodash, Remeda, Radashi) · head (es-toolkit, Ramda, Effect) · ❌ (Modern Dash)
Example
const numbers = [1, 2, 3, 4, 5];
// ❌ Deprecated approach
const firstElement = first(numbers);
console.log(firstElement); // 1
// ✅ Recommended approach
const firstNative = numbers[0];
console.log(firstNative); // 1
// ✅ Modern approach with ES2022
const firstModern = numbers.at(0);
console.log(firstModern); // 1
How it works?
Gets the first element of an array. Alias for head.
Deprecated: Use array[0] or array.at(0) directly.
Native Equivalent
// ❌ first(arr)
// ✅ arr[0]
// ✅ arr.at(0) // ES2022
Use Cases
Get default selection from lists 📌
Retrieve the first element as the default selected item.
const countries = ["United States", "Canada", "Mexico"];
countries[0];
// => "United States"
Extract primary result from search
Get the top/most relevant result from a search response.
const searchResults = [{ title: "Best Match", score: 0.98 }, ...];
searchResults[0];
// => { title: "Best Match", score: 0.98 }
Get primary validation error
Extract the first validation error to display.
const errors = [{ field: "email", message: "Invalid" }, ...];
errors[0];
// => { field: "email", message: "Invalid" }