object-deep-merge

Strongly-typed deep and recursive object merging with support for all value types.

Install

``bash
pnpm add object-deep-merge
`

`bash
yarn add object-deep-merge
`

`bash
npm install object-deep-merge
`

Basic Usage

`ts
import { merge } from "object-deep-merge";
`

$3

`ts
const merged = merge({ foo: false }, { bar: true });

console.log({ merged });
`

Typed Usage

$3

The merge function accepts two optional type generics. TData and TResult.

`ts
function merge(
source: TData,
target: TData,
...targets: Array
): TResult;
`

> [!IMPORTANT]
> The Merge and MergeDeep types from type-fest are great additions to this library. It is not unreasonable to use those types for your merge typing needs.

Without explicitly passing in types the function will infer the shape of the object(s) passed in.

- Passing in TData will validate the shape of the objects passed in.
- Passing in TResult will override the output type. While this should be used sparingly, it provides a convenient approach for correctly typing partial types into complete types.

$3

`ts
type Data = {
name: string;
description: string;
};

const base: Data = { name: "object-deep-merge", description: "merge objects" };

const overrides: Partial = { description: "merge objects, deeply" };

const merged = merge(base, overrides);

// Type is inferred so the signature becomes:
// function merge, Partial>(source: Partial, target: Partial, ...targets: Partial[]): Partial

// TData = Partial
// TResult = Data

console.log({ merged });
`

$3

> [!NOTE]
> Passing in TData will validate the shape of the objects passed in.

`ts
type Data = {
name: string;
description: string;
};

const base: Data = { name: "object-deep-merge", description: "merge objects" };

const overrides: Partial = { description: "merge objects, deeply" };

const merged: Partial = merge>(base, overrides);

// TData = Partial
// TResult = Data

console.log({ merged });
`

$3

> [!NOTE]
> Passing in TResult will override the output type. While this should be used sparingly, it provides a convenient approach for correctly typing partial types into complete types.

`ts
type Data = {
name: string;
description: string;
};

const base: Data = { name: "object-deep-merge", description: "merge objects" };

const overrides: Partial = { description: "merge objects, deeply" };

const merged: Data = merge, Data>(base, overrides);

// TData = Partial
// TResult = Data

console.log({ merged });
`