Benchmark: lodash defaults vs spread

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', c: 'word' }; var b = { c: 'goddess' }; var c = _.defaults(a, b);
spread
var a = { a: 'oh', b: 'my', c: 'word' }; var b = { c: 'goddess' }; var c = { ...b, ...a };

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lodash merge
spread

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:135.0) Gecko/20100101 Firefox/135.0

Browser/OS: Firefox 135 on Windows

View result in a separate tab

Test name	Executions per second
lodash merge	6956036.5 Ops/sec
spread	6392860.0 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):

LLMs can make mistakes. Check important info.

Let's break down the provided JSON and explain what's being tested.

**Benchmark Definition**

The benchmark is called "lodash defaults vs spread" and it compares two approaches to merging objects: using the `_.defaults` function from Lodash and using the spread operator (`...`) with object destructuring.

**Options Compared**

There are two options compared:

1. **Lodash `.defaults()`**: This method takes two or more objects as arguments and returns a new object that contains all the properties from the input objects, with the values coming from the first object where the property exists.
2. **Spread Operator (`...`) with Object Destructuring**: This approach uses the spread operator to create a new object by copying the properties from one object (in this case, `b`) and then merging them with the properties from another object (in this case, `a`).

**Pros and Cons of Each Approach**

1. **Lodash `.defaults()`**:
	* Pros: Convenient and efficient way to merge objects.
	* Cons: Requires Lodash library to be included, which may add extra overhead.
2. **Spread Operator (`...`) with Object Destructuring**:
	* Pros: Native JavaScript implementation, no additional library required.
	* Cons: May be less readable or maintainable than the Lodash approach.

**Library and its Purpose**

The `_.defaults()` function is part of the Lodash library, which provides a set of utility functions for functional programming. In this context, it's used to merge objects by copying properties from one object to another.

**Special JS Feature/Syntax**

None mentioned in the provided code snippets.

**Other Considerations**

When comparing these two approaches, consider the following:

* **Performance**: Lodash `.defaults()` is likely to be faster than the spread operator approach since it's implemented in native JavaScript and doesn't require function calls or object creation.
* **Readability and Maintainability**: The spread operator approach may be less readable for complex object mergers, while the Lodash approach can make it easier to understand and maintain.

**Alternatives**

If you prefer not to use the spread operator or want a more concise way to merge objects, consider using:

1. `Object.assign()`: This method takes one or more source objects and merges them into a target object.
2. `Object.create()`: This method creates a new object that inherits properties from an existing object.
3. Another library like Immutable.js (which provides a robust set of utilities for working with immutable data structures).

These alternatives can provide different trade-offs in terms of performance, readability, and maintainability compared to the Lodash `.defaults()` approach or the spread operator method.

Related benchmarks:

lodash defaults vs spread (version: 0)

Comparing performance of: lodash merge vs spread

Created: 6 years ago by: Guest

Jump to the latest result

lodash merge

spread

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):