Benchmark: Lodash vs reduce Map()

HTML Preparation code:

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

Script Preparation code:

var max2 = 100000;

var data = [];
for (var i = 0; i <= max2; i++) { data.push({ id: i }); }

Tests:

Lodash
_.groupBy(data, ({ id }) => id)
Foreach Map
const test = new Map(); data.forEach((item) => { test.set(item.id, item) })

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Lodash
Foreach 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):

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

**Overview**
The benchmark is designed to compare the performance of two approaches: using Lodash's `groupBy` function and using a manual approach with a `Map` data structure. The goal is to determine which method is faster for grouping an array of objects by their `id` property.

**Script Preparation Code**
The script preparation code creates an array of 100,000 objects with an `id` property ranging from 0 to 99,999. This is done using a simple `for` loop and the `push` method.

**Html Preparation Code**
The HTML preparation code includes a reference to Lodash's `lodash.min.js` library, which will be used for the Lodash-based test case.

**Test Cases**

### Test Case 1: Lodash

```javascript
_.groupBy(data, ({ id }) => id)
```

This line uses Lodash's `groupBy` function to group the `data` array by the `id` property. The function takes a predicate as an argument, which returns the value of the `id` property for each object in the array.

**Pros:**

* Easy to read and maintain
* Optimized for performance by using Lodash's internal implementation

**Cons:**

* Requires an additional library dependency (Lodash)
* May have overhead due to the external library

### Test Case 2: Foreach Map

```javascript
const test = new Map();
data.forEach((item) => {
  test.set(item.id, item);
})
```

This code creates a new `Map` data structure and iterates over the `data` array using the `forEach` method. For each object in the array, it sets the `id` property as the key and the entire object as the value.

**Pros:**

* No additional library dependency required
* Uses built-in JavaScript data structures

**Cons:**

* May be slower due to manual iteration and mapping
* Requires more code and maintenance effort

**Library: Lodash's `groupBy` function**
The `groupBy` function is a utility function from the Lodash library that groups an array of objects by a specified property. It returns a new object with the grouped values.

**Special JS Feature or Syntax: None**
There are no special JavaScript features or syntax used in these test cases.

**Other Alternatives**

* Using other group-by functions, such as `Array.prototype.reduce()` or `Array.prototype.forEach()`, might be viable alternatives.
* Implementing a custom grouping function using recursion or other techniques could also be explored.

In conclusion, the benchmark compares two approaches for grouping an array of objects by their `id` property. Lodash's `groupBy` function provides an optimized and easy-to-use solution, while the manual `Map` approach offers a lightweight alternative with no additional library dependency required.

Related benchmarks:

Lodash vs reduce Map() (version: 0)

Comparing performance of: Lodash vs Foreach Map

Created: 4 years ago by: Guest

Jump to the latest result

Lodash

Foreach 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):