Benchmark: unionbyb - MeasureThat.net

HTML Preparation code:

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

Script Preparation code:

var users = [
  { 'name': 'barney',  'age': 36 },
];

var newUsers = [
  { 'name': 'fred',    'age': 40 },
  { 'name': 'barney',  'age': 36 },
  { 'name': 'pebbles', 'age': 2 }
];

for(let i = 0; i < 2000; i++) {
  var newUser = { 'name': 'user_' + i, 'age': Math.floor(Math.random() * i) };
  newUsers.push(newUser);
  users.push(newUser)
}

Tests:

loadash
const unionUsers2 = _.unionBy(newUsers, users, 'name'); console.log('ub', unionUsers2.length)
forEach
let obj = {} users.forEach((user) => obj[user.name] = user) newUsers.forEach((user) => obj[user.name] = user) console.log('test', Object.values(obj).length)
my
let s = new Set(); let m = new Map(); let un = []; users.forEach((user) => { if (m[user.name]) return; m[user.name] = true; un.push(user); }) newUsers.forEach((user) => { if (m[user.name]) return; m[user.name] = true; un.push(user); }) console.log('test', un.length)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
loadash
forEach
my

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.

Let's break down the provided JSON and explain what is tested, the different approaches compared, their pros and cons, and other considerations.

**Benchmark Definition**

The benchmark definition represents a JavaScript microbenchmark that measures the performance of various approaches for merging two arrays while removing duplicates based on a common key. The script preparation code generates an array `users` with 36 elements and another array `newUsers` with 2000 elements, each containing a unique name and age.

**Approaches Compared**

The benchmark compares three different approaches to merge the two arrays:

1. **Lodash's `unionBy` function**: This approach uses Lodash's `unionBy` function, which takes three arguments: the two arrays to be merged (`newUsers` and `users`) and a common key (`'name'`) to remove duplicates.
2. **Loop-based approach using `forEach`**: This approach iterates through both arrays using the `forEach` method, checking if each user already exists in the merged array (using a Map or Set), and adding new users if they don't exist.
3. **Loop-based approach using a Set and a Map**: Similar to the previous approach, but uses a Set and a Map to keep track of existing users.

**Pros and Cons**

1. **Lodash's `unionBy` function**:
	* Pros: Efficient, concise, and well-maintained.
	* Cons: Requires Lodash library to be loaded, which may add unnecessary overhead.
2. **Loop-based approach using `forEach`**:
	* Pros: Easy to implement, intuitive, and doesn't require additional libraries.
	* Cons: May be slower due to the need to check for existing users in each iteration.
3. **Loop-based approach using a Set and a Map**:
	* Pros: Similar performance to Lodash's `unionBy` function, but avoids external library dependencies.
	* Cons: More complex implementation, requires manual error handling.

**Library: Lodash**

Lodash is a popular JavaScript utility library that provides various functions for tasks such as array manipulation, string trimming, and more. In this benchmark, the `unionBy` function is used to merge the two arrays while removing duplicates based on the `'name'` key.

**Special JS Feature/Syntax**

There are no special JS features or syntaxes mentioned in the benchmark definition or test cases.

**Other Alternatives**

If you're looking for alternatives to Lodash's `unionBy` function, you could consider:

* Using the `Set` data structure and iterating through both arrays using `forEach`.
* Implementing your own custom merge function using a loop-based approach.
* Utilizing other libraries or frameworks that provide similar functionality.

Keep in mind that the choice of approach depends on the specific requirements of your project and personal preferences.

Related benchmarks:

unionbyb (version: 0)

Comparing performance of: loadash vs forEach vs my

Created: 2 years ago by: Guest

Jump to the latest result

loadash

forEach

my

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):