findAndReplace

The findAndReplace() function searches for the first element that satisfies a predicate, replaces it with a new value, and returns the updated array. If no element matches, it returns undefined.

Interactive example

Syntax

Classic signature

function findAndReplace<
  GenericArray extends readonly unknown[],
  GenericValue extends AnyValue,
>(
  input: GenericArray,
  predicate: (
    element: GenericArray[number],
    params: { index: number }
  ) => boolean,
  value: GenericValue,
): (GenericArray[number] | GenericValue)[] | undefined

Curried signature

function findAndReplace<
  GenericArray extends readonly unknown[],
  GenericValue extends AnyValue,
>(
  predicate: (
    element: GenericArray[number],
    params: { index: number }
  ) => boolean,
  value: GenericValue,
): (input: GenericArray) => (GenericArray[number] | GenericValue)[] | undefined

Parameters

• input: Source array.
• predicate: Function called for each element with the element and its index. Must return true when the element is targeted.
• value: New value that replaces the found element.

Return value

A new array with the element replaced, or undefined if no element satisfies the predicate.

See also

• find - Finds the first element that satisfies a condition
• findAndSpliceReplace - Replaces a segment via splice