maxBy (Functional Programming)

Creates a function that returns the value with the largest computed score. Use it with pipe.

const result = pipe(array, maxBy(getValue));

::: info

Prefer the original es-toolkit maxBy in ordinary code. Use this fp variant when composing transformations with pipe.

:::

Usage

maxBy calls getValue for each value in the piped array and returns the value with the largest result. If the array is empty, it returns undefined.

import { maxBy, pipe } from 'es-toolkit/fp';

pipe(
  [{ score: 10 }, { score: 30 }, { score: 20 }],
  maxBy(item => item.score)
); // => { score: 30 }

Parameters

• getValue ((item: T) => number): The function that returns the value used for comparison.

Returns

((array: readonly T[]) => T | undefined): A function that maps a readonly T[] to the maximum item, or undefined.