# concat-merge

[![test workflow](https://github.com/ambar/concat-merge/actions/workflows/test.yml/badge.svg)](https://github.com/ambar/concat-merge/actions/workflows/test.yml)

Recursively merge objects, especially for webpack/rollup configs.

## Comparison

| name | immutable | concat | dedupe | clone | multiple parameters | recommended |
| ----------------------------------------------------------------------------------------------------------------------------------------------------------- | --------- | ---------------- | ---------------- | ---------------- | ------------------- | ----------- |
| concat-merge [![concat-merge](https://img.shields.io/bundlephobia/minzip/concat-merge)](https://bundlephobia.com/package/concat-merge) | `true` | `true` | `false` | `true` | no | yes |
| merge-deep [![merge-deep](https://img.shields.io/bundlephobia/minzip/merge-deep)](https://bundlephobia.com/package/merge-deep) | `true` | `true` | `true` | `true` | yes | yes |
| deepmerge [![deepmerge](https://img.shields.io/bundlephobia/minzip/deepmerge)](https://bundlephobia.com/package/deepmerge) | `true` | `true` | `false` | `false` (option) | no | |
| lodash/merge [![lodash.merge](https://img.shields.io/bundlephobia/minzip/lodash.merge)](https://bundlephobia.com/package/lodash.merge) | `false` | `false` | `false` | `true` | yes | |
| lodash/mergeWith [![lodash.mergewith](https://img.shields.io/bundlephobia/minzip/lodash.mergewith)](https://bundlephobia.com/package/lodash.mergewith) | `false` | `false` (option) | `false` (option) | `true` | yes | yes |

## Install

```
npm install concat-merge
```

## Usage

```js
import concatMerge from 'concat-merge'

concatMerge(baseConfig, {
 input: 'entry.js',
 plugins: [inject({React: 'react'})],
})
```

lodash equivalent:

```js
import mergeWith from 'lodash/mergeWith'

const concatMerge = (...args) =>
 mergeWith({}, ...args, (prev, next) => {
 if (Array.isArray(prev)) {
 return prev.concat(next)
 }
 })
```

concat-merge

ambarli

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Bin script confusion

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Chrome Extension Content Script

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High entropy strings

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Network access

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concat-merge

concat-merge

Comparison

Install

Usage

Keywords

Related posts

name	immutable	concat	dedupe	clone	multiple parameters	recommended
concat-merge	`true`	`true`	`false`	`true`	no	yes
merge-deep	`true`	`true`	`true`	`true`	yes	yes
deepmerge	`true`	`true`	`false`	`false` (option)	no
lodash/merge	`false`	`false`	`false`	`true`	yes
lodash/mergeWith	`false`	`false` (option)	`false` (option)	`true`	yes	yes

concat-merge

concat-merge

Comparison

Install

Usage

Keywords

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