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

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

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 27 days ago):

LLMs can make mistakes. Check important info.

Let's break down the benchmark and its options.

The test case is comparing two approaches to transform an object by changing its property names using JavaScript:

1. **`lodash.mapKeys`**: This approach uses the `lodash` library, which provides a utility function `mapKeys` that applies a mapping function to each key of an object.
2. **Native iteration with `for...of` loop**: This approach uses native JavaScript features to iterate over the properties of an object and transform them.

**Pros and Cons:**

**Lodash `mapKeys`:**

Pros:

* Provides a concise and readable way to perform transformations on objects using a mapping function.
* The library is well-maintained, widely used, and has a large community of contributors.
* It abstracts away the underlying iteration mechanism, making it easier to reason about the code.

Cons:

* Introduces an external dependency (the `lodash` library), which may not be desirable for all projects or environments.
* May have performance implications due to the overhead of calling a function from a library.

**Native iteration with `for...of` loop:**

Pros:

* No external dependencies, making it more suitable for projects that want to avoid adding extra libraries.
* Directly utilizes native JavaScript features, which may lead to better performance and more efficient code generation.
* Easy to understand and maintain, as the logic is straightforward.

Cons:

* Requires a deeper understanding of JavaScript iteration mechanisms and the intricacies of property access.
* The code can become verbose and harder to read due to the explicit loop structure.

**Other Considerations:**

* The use of `Object.keys()` to iterate over object properties might not be the most efficient approach, as it can lead to additional overhead due to the creation of a new array of keys. A native iteration with `for...of` loop avoids this potential issue.
* Lodash's `mapKeys` function creates a new object and iterates over its entries, whereas the native approach directly transforms the original object.

**Library and its purpose:**

The library used in this benchmark is Lodash (`lodash`). Its primary purpose is to provide a set of utility functions for functional programming, data manipulation, and other common tasks. In this specific case, `mapKeys` is a function that applies a mapping function to each key of an object, returning a new object with transformed keys.

**Special JavaScript feature or syntax:**

This benchmark does not explicitly test any special JavaScript features or syntax beyond the standard iteration mechanisms and library usage.

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.183 Safari/537.36

Browser/OS: Chrome 86 on Mac OS X 10.14.6

View result in a separate tab

Test name	Executions per second
lodash.mapKeys	1031054.2 Ops/sec
native	1223893.8 Ops/sec

Related benchmarks:

lodash.mapKeys vs Iterating over properties in for of loop in function (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 27 days ago):