Benchmark: create temp object vs Object.fromEntries

Script Preparation code:

var array = Array.from(Array(10000).keys()).map(i => {
    var length = Math.round(Math.random()*100)
    var result           = '';
    var characters       = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
    var charactersLength = characters.length;
    for ( var i = 0; i < length; i++ ) {
      result += characters.charAt(Math.floor(Math.random() * 
 charactersLength));
   }
   return result;
})

AخA
 
var array = Array.from(Array(10000).keys()).map(i => {    var length = Math.round(Math.random()*100)    var result           = '';    var characters       = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';    var charactersLength = characters.length;    for ( var i = 0; i < length; i++ ) {      result += characters.charAt(Math.floor(Math.random() *  charactersLength));   }   return result;})

Tests:

Object.fromEntries
Object.fromEntries(array.map(value => [value, value]));
Object.fromEntries(array.map(value => [value, value]));
creating temporary objects
const data = {} array.forEach(value => data[value] = value);
const data = {}
array.forEach(value => data[value] = value);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Experimental features:

Memory measurements supported only in Chrome.
For precise memory measurements Chrome must be launched with --enable-precise-memory-info flag.
More information: Monitoring JavaScript Memory

Test case name	Result
Object.fromEntries
creating temporary objects

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.77 Safari/537.36

Browser/OS: Chrome 91 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Object.fromEntries	936.6 Ops/sec
creating temporary objects	1597.7 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):

I'll break down the provided benchmark and explain what's being tested, compared options, pros and cons of each approach, and other considerations.

Benchmark Overview

The benchmark is comparing two approaches for creating an object with dynamic key-value pairs:

Object.fromEntries (a built-in JavaScript method)
Creating a temporary object using the forEach loop and direct assignment (data[value] = value)

Options Being Compared

Two options are being compared:

Option 1: Object.fromEntries
- Purpose: Create an object from key-value pairs provided as an array of entries.
- Description: Passes an array of key-value pairs to the Object.fromEntries method, which returns a new object with the specified keys and values.
Option 2: Creating temporary objects using the forEach loop
- Purpose: Create a temporary object by iterating over an array using the forEach loop and assigning each value as a key-value pair in the object.

Pros and Cons of Each Approach

Object.fromEntries

Pros:

Concise and readable: The syntax is straightforward, making it easy to understand for developers.
Fast performance: As this method is built-in, it's likely optimized for performance.

Cons:

Limited control: The Object.fromEntries method returns a new object, so you don't have direct access to the underlying data structure.

Creating Temporary Objects using forEach

Pros:

Flexibility: You can directly modify or inspect the temporary object as needed.
Low overhead: No additional methods are called, making it potentially more efficient than Object.fromEntries.

Cons:

Verbose syntax: The code is less readable and more verbose compared to Object.fromEntries.
Potential performance issues: Depending on the specific use case, creating a temporary object using forEach might lead to unnecessary memory allocations or garbage collection.

Library/Dependencies

None mentioned in this benchmark definition.

Special JS Features/Syntax

The benchmark uses JavaScript syntax and features, such as:

Array.from() method
map() method
forEach() loop

These are standard JavaScript features and don't require special knowledge to understand.

Other Alternatives

If the goal is to create an object with dynamic key-value pairs, other alternatives might include:

Using a library like Lodash or Ramda for functional programming utilities.
Utilizing a different data structure, such as a Map or a WeakMap (if you're targeting modern browsers).
Implementing a custom solution using JavaScript's built-in data structures and methods.

For this specific benchmark, the focus is on comparing two approaches: Object.fromEntries and creating temporary objects using forEach.

LLMs can make mistakes. Check important info.

I'll break down the provided benchmark and explain what's being tested, compared options, pros and cons of each approach, and other considerations.

**Benchmark Overview**

The benchmark is comparing two approaches for creating an object with dynamic key-value pairs:

1. `Object.fromEntries` (a built-in JavaScript method)
2. Creating a temporary object using the `forEach` loop and direct assignment (`data[value] = value`)

**Options Being Compared**

Two options are being compared:

* **Option 1: `Object.fromEntries`**
	+ Purpose: Create an object from key-value pairs provided as an array of entries.
	+ Description: Passes an array of key-value pairs to the `Object.fromEntries` method, which returns a new object with the specified keys and values.
* **Option 2: Creating temporary objects using the `forEach` loop**
	+ Purpose: Create a temporary object by iterating over an array using the `forEach` loop and assigning each value as a key-value pair in the object.

**Pros and Cons of Each Approach**

### Object.fromEntries

Pros:

1. **Concise and readable**: The syntax is straightforward, making it easy to understand for developers.
2. **Fast performance**: As this method is built-in, it's likely optimized for performance.

Cons:

1. **Limited control**: The `Object.fromEntries` method returns a new object, so you don't have direct access to the underlying data structure.

### Creating Temporary Objects using forEach

Pros:

1. **Flexibility**: You can directly modify or inspect the temporary object as needed.
2. **Low overhead**: No additional methods are called, making it potentially more efficient than `Object.fromEntries`.

Cons:

1. **Verbose syntax**: The code is less readable and more verbose compared to `Object.fromEntries`.
2. **Potential performance issues**: Depending on the specific use case, creating a temporary object using `forEach` might lead to unnecessary memory allocations or garbage collection.

**Library/Dependencies**

None mentioned in this benchmark definition.

**Special JS Features/Syntax**

The benchmark uses JavaScript syntax and features, such as:

1. `Array.from()` method
2. `map()` method
3. `forEach()` loop

These are standard JavaScript features and don't require special knowledge to understand.

**Other Alternatives**

If the goal is to create an object with dynamic key-value pairs, other alternatives might include:

1. Using a library like Lodash or Ramda for functional programming utilities.
2. Utilizing a different data structure, such as a Map or a WeakMap (if you're targeting modern browsers).
3. Implementing a custom solution using JavaScript's built-in data structures and methods.

For this specific benchmark, the focus is on comparing two approaches: `Object.fromEntries` and creating temporary objects using `forEach`.

Related benchmarks:

create temp object vs Object.fromEntries (version: 0)

Comparing performance of: Object.fromEntries vs creating temporary objects

Created: 3 years ago by: Guest

Jump to the latest result

Object.fromEntries

creating temporary objects

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):

Object.fromEntries

Creating Temporary Objects using forEach