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merge

This method is like assign except that it recursively merges own and inherited enumerable string keyed properties of source objects into the destination object.

Source properties that resolve to undefined are skipped if a destination value exists.

Array and plain object properties are merged recursively.

Other objects and value types are overridden by assignment.

Source objects are applied from left to right.

Subsequent sources overwrite property assignments of previous sources.

Note: This method mutates object.

API

type ObjTypeWithAny = Record<string, any>;

function merge<T extends ObjTypeWithAny, U extends ObjTypeWithAny>(
target: T,
source: U
): T & U;

Usage

import { merge } from "@feedzai/js-utilities";

const object = {
'a': [{ 'b': 2 }, { 'd': 4 }]
}

const other = {
'a': [{ 'c': 3 }, { 'e': 5 }]
}

merge(object, other)
// => { 'a': [{ 'b': 2, 'c': 3 }, { 'd': 4, 'e': 5 }] }