Toggle navigation
MeasureThat.net
Create a benchmark
Tools
Feedback
FAQ
Register
Log In
Cloning array: Array.from vs spread (correction)
(version: 0)
Comparing performance of:
Array.from vs Spread
Created:
6 years ago
by:
Registered User
Jump to the latest result
Script Preparation code:
const array = window.array = Array(1000) for (let i = 0; i !== array.length; ++i) array[i] = i
Tests:
Array.from
window.a = Array.from(array)
Spread
window.b = [...array]
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (2)
Previous results
Fork
Test case name
Result
Array.from
Spread
Fastest:
N/A
Slowest:
N/A
Latest run results:
No previous run results
This benchmark does not have any results yet. Be the first one
to run it!
Autogenerated LLM Summary
(model
llama3.2:3b
, generated one year ago):
**Benchmark Overview** The provided benchmark, "Cloning array: Array.from vs spread (correction)", is designed to measure the performance difference between two methods for cloning an array in JavaScript: `Array.from()` and the spread operator (`...`). The benchmark aims to create a large array of 1000 elements, populate it with sequential values, and then clone it using each of the two methods. **Benchmark Preparation Code** The script preparation code creates a large array of 1000 elements, populated with sequential values from 0 to 999. This is done using a `for` loop that iterates over the length of the array: ```javascript const array = window.array = Array(1000) for (let i = 0; i !== array.length; ++i) array[i] = i ``` This step is crucial as it sets up the test case with a large, populated array that will be cloned. **Individual Test Cases** There are two test cases: 1. `Array.from`: Clones the array using the `Array.from()` method. 2. `Spread`: Clones the array using the spread operator (`...`). The benchmark definition for each test case is included in the provided JSON data. **Options Compared** In this benchmark, we have two options compared: * `Array.from()`: This method creates a new array from an iterable or an array-like object. In this case, it's used to clone the original array. * Spread operator (`...`): This operator creates a new array by spreading the elements of an array. **Pros and Cons** * **Array.from()**: + Pros: It's a more modern and efficient method for cloning arrays in recent versions of JavaScript. It also provides additional options, such as allowing you to specify the type of elements to extract from the original array. + Cons: It might be slower than the spread operator due to the overhead of creating an iterator object. * **Spread operator (`...`)**: + Pros: It's a concise and expressive way to clone arrays. It also works in older versions of JavaScript, as it's based on the array iteration syntax that was available from the start. + Cons: It might be slower than `Array.from()` due to the overhead of creating an iterator object. **Library Used** There is no library used in this benchmark. **Special JS Feature/Syntax** None mentioned. The benchmark only uses standard JavaScript features and syntax. **Other Alternatives** If you're looking for alternative ways to clone arrays, here are a few options: * `Array.prototype.slice()`: This method creates a shallow copy of the original array. * `JSON.parse(JSON.stringify(array))`: This method creates a deep copy of the original array. Note that this method can be slower than the spread operator due to the overhead of parsing and stringifying the array. Keep in mind that these alternatives might have different performance characteristics compared to the spread operator, so you should test them to determine which one is best for your specific use case.
Related benchmarks:
Cloning array: Array.from vs spread
Cloning array: Array.from vs spread corrected
Slice vs spread array
Array cloning 2023
Comments
Confirm delete:
Do you really want to delete benchmark?