Benchmark: Map vs lodash.uniq

HTML Preparation code:

script src='https://cdn.jsdelivr.net/npm/lodash@4.17.10/lodash.min.js'></script>

Tests:

lodash.uniq
const arr = [{id: 1}, {id: 2}, {id: 3}, {id: 1}, {id: 2}, {id: 3}, {id: 1}, {id: 2}, {id: 3}]; return _.uniqBy(arr, el => el.id);
Map
const arr = [{id: 1}, {id: 2}, {id: 3}, {id: 1}, {id: 2}, {id: 3}, {id: 1}, {id: 2}, {id: 3}]; return (new Map(arr.map(el => [el.id, el]))).values

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lodash.uniq
Map

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.

I'd be happy to help you understand the benchmark test.

**What is being tested?**

The provided JSON represents a JavaScript microbenchmarking test created on MeasureThat.net. The test compares two approaches: `lodash.uniq` and `Map`. Both functions are designed to remove duplicate elements from an array based on a specific property (in this case, the `id` property).

**Options compared:**

1. **`lodash.uniq`**: A popular JavaScript library that provides a convenient way to remove duplicates from arrays.
2. **`Map`**: A built-in JavaScript data structure that allows us to store key-value pairs.

**Pros and Cons of each approach:**

1. **`lodash.uniq`**:
	* Pros:
		+ Convenient and easy to use.
		+ Well-tested and widely adopted.
	* Cons:
		+ Adds an external dependency (the `lodash` library).
		+ May have performance overhead due to the library's complexity.
2. **`Map`**:
	* Pros:
		+ No external dependencies.
		+ Can be more efficient for large datasets, as it avoids the need to iterate over the array twice.
	* Cons:
		+ Requires a basic understanding of JavaScript data structures and iteration.

**Other considerations:**

1. **Memory usage**: `lodash.uniq` creates a new array with unique elements, which can lead to increased memory usage for large datasets. In contrast, `Map` only uses additional memory for the key-value pairs stored in the map.
2. **Performance**: For very large datasets, `Map` might be faster due to its ability to avoid duplicate checks. However, for smaller datasets or when using a well-optimized library like `lodash`, the performance difference may be negligible.

**Library:**

In this test, `lodash.uniq` is used as a JavaScript library that provides a convenient way to remove duplicates from arrays. It's a popular and widely adopted library, but it does add an external dependency to the test.

**Special JS feature or syntax:**

There are no special JavaScript features or syntaxes being tested in this benchmark. Both approaches rely on standard JavaScript data structures (arrays and maps) and basic iteration logic.

**Alternatives:**

If you want to explore alternative approaches, here are a few options:

1. **`Set`**: A built-in JavaScript data structure that can be used to remove duplicates from an array.
2. **`Filter` and `Reduce`**: These methods can be used to remove duplicates by filtering out elements that already exist in the result set.
3. **Custom implementation using `for...of` loops**: You could write a custom loop-based implementation to remove duplicates, but this would likely be less efficient than using an existing library like `lodash` or leveraging built-in data structures like `Map`.

Keep in mind that these alternatives may not offer the same level of convenience and performance as the original approaches tested on MeasureThat.net.

Related benchmarks:

Map vs lodash.uniq (version: 0)

Comparing performance of: lodash.uniq vs Map

Created: 3 years ago by: Guest

Jump to the latest result

lodash.uniq

Map

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):