Benchmark: lodash.mapKeys vs Iterating over properties in for of loop

HTML Preparation code:

<script src="https://cdn.jsdelivr.net/lodash/4.16.0/lodash.min.js"></script>

Script Preparation code:

var value = {a: 30310, b: 100303, c: 3040494};

Tests:

lodash.mapKeys
_.mapKeys(value, k => k + '-changed')
native
const m = {} for (const k of Object.keys(value)) { m[k + '-changed'] = value[k] }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lodash.mapKeys
native

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark definition and test cases.

**Benchmark Definition and Script Preparation Code**

The benchmark is defined as `_.mapKeys(value, k => k + '-changed')`, which uses the Lodash library to map keys in an object. The script preparation code provides a sample object `value` with three properties: `a`, `b`, and `c`.

**Html Preparation Code**

The HTML preparation code includes a link to load the Lodash library, version 4.16.0, which is used by the benchmark.

**Test Cases**

There are two individual test cases:

1. **Lodash.mapKeys**: This test case uses the `_.mapKeys` function from the Lodash library to map keys in the `value` object.
2. **Native**: This test case implements the same mapping logic using a `for...of` loop and an empty object `m`.

**What is tested?**

The benchmark tests two approaches to perform a simple key-value transformation on an object:

* Using the Lodash library's `_.mapKeys` function, which is a higher-order function that takes a callback function as an argument.
* Implementing the same logic using a native JavaScript `for...of` loop and an empty object.

**Options compared**

The two test cases compare the performance of two different approaches:

1. **Lodash.mapKeys**: Uses the Lodash library's optimized implementation, which is likely to be faster due to its compilation and caching capabilities.
2. **Native**: Implements the logic using native JavaScript, without any external dependencies or optimizations.

**Pros and Cons**

* **Lodash.mapKeys**:
	+ Pros: Faster execution time (thanks to optimization and caching), less boilerplate code required, easier maintenance.
	+ Cons: Requires an additional library dependency, may introduce performance overhead due to lazy loading or parsing.
* **Native**:
	+ Pros: No additional dependencies, likely to be more familiar to developers, can be optimized further for specific use cases.
	+ Cons: More verbose code, requires manual optimization and caching (if needed), potential performance differences.

**Library used**

The benchmark uses the Lodash library, which is a popular utility library that provides various functions for functional programming, data manipulation, and more.

**Special JS feature or syntax**

There are no specific JavaScript features or syntax mentioned in the benchmark. However, it's worth noting that the `for...of` loop used in the native test case is a relatively modern feature introduced in ECMAScript 2015 (ES6).

**Other alternatives**

If you were to rewrite this benchmark without using Lodash, you could consider other alternatives such as:

* Using the built-in `Object.keys()` and `forEach()` methods.
* Implementing a custom mapping function using a simple loop or recursion.
* Using a different library or framework that provides similar functionality.

Keep in mind that these alternatives may require additional setup or dependencies, and their performance might vary compared to the Lodash implementation.

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.36

Browser/OS: Chrome 119 on Windows

View result in a separate tab

Test name	Executions per second
lodash.mapKeys	2791268.0 Ops/sec
native	3269935.0 Ops/sec

Related benchmarks:

lodash.mapKeys vs Iterating over properties in for of loop (version: 0)

Comparing performance of: lodash.mapKeys vs native

Created: 4 years ago by: Guest

Jump to the latest result

lodash.mapKeys

native

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):