Benchmark: spread vs assign vs _.merge vs for

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Tests:

lodash merge
var a = { a: 'oh', b: 'my', a2: 'oh', b2: 'my' }; var b = { c: 'goddess', c2: 'goddess', c3: 'goddess' }; var c = _.merge(a, b);
object.assign
var a = { a: 'oh', b: 'my', a2: 'oh', b2: 'my' }; var b = { c: 'goddess', c2: 'goddess', c3: 'goddess' }; var c = Object.assign({}, a, b);
spread
var a = { a: 'oh', b: 'my', a2: 'oh', b2: 'my' }; var b = { c: 'goddess', c2: 'goddess', c3: 'goddess' }; var c = { ...a, ...b };
for
var a = { a: 'oh', b: 'my', a2: 'oh', b2: 'my' }; var b = { c: 'goddess', c2: 'goddess', c3: 'goddess' }; for (let key in b) { a[key] = b[key]; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lodash merge
object.assign
spread
for

Fastest: N/A

Slowest: N/A

Latest run results:

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Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Let's break down what's being tested in the provided benchmark.

The benchmark is comparing four different approaches to merge two objects:

1. `_.merge` from Lodash (a JavaScript library)
2. `Object.assign`
3. The spread operator (`{ ... }`)
4. A manual loop using `for...in`

Each approach has its pros and cons:

**Lodash _.merge**

Pros:

* Concise and readable syntax
* Handles nested objects automatically
* Can be used with other Lodash functions

Cons:

* Requires importing the Lodash library
* May have slower performance compared to native JavaScript methods

**Object.assign**

Pros:

* Native JavaScript method, optimized for performance
* Works with any object type (not just simple objects)
* Simple and readable syntax

Cons:

* Does not handle nested objects automatically
* Returns a new object, which may be unnecessary in some cases

**Spread Operator (`{ ... }`)**

Pros:

* Concise and expressive syntax
* Handles nested objects automatically
* Works with any object type (not just simple objects)
* Fast and efficient performance

Cons:

* Requires modern JavaScript support (ES6+)
* May not work as expected in older browsers or environments

**Manual Loop using `for...in`**

Pros:

* Works in all browsers and environments that support JavaScript
* No additional libraries required
* Can be optimized for specific use cases

Cons:

* Less concise and less readable syntax
* Requires manual handling of nested objects
* May have slower performance compared to native JavaScript methods

In the provided benchmark, each approach is being tested with two simple object merge examples. The results will show which approach performs best in terms of execution speed.

As for special JS features or syntax used, none are mentioned explicitly in the benchmark definition. However, the spread operator (`{ ... }`) requires modern JavaScript support (ES6+), while Lodash's `_.merge` and `Object.assign` do not have any specific feature requirements.

The alternative approaches to merging objects include:

* Using a library like jQuery or another DOM manipulation library
* Using a functional programming approach, such as with Immutable.js
* Using a custom implementation that takes into account specific use case requirements

Keep in mind that the best approach will depend on the specific requirements and constraints of your project.

Related benchmarks:

spread vs assign vs _.merge vs for (version: 0)

Comparing performance of: lodash merge vs object.assign vs spread vs for

Created: 3 years ago by: Guest

Jump to the latest result

lodash merge

object.assign

spread

for

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):