Toggle navigation
MeasureThat.net
Create a benchmark
Tools
Feedback
FAQ
Register
Log In
Array keys spread vs for
(version: 0)
Comparing performance of:
Array keys spread vs for
Created:
4 years ago
by:
Registered User
Jump to the latest result
Tests:
Array keys spread
const arr = []; [...Array(10).keys()].forEach((i) => { arr.push(i); });
for
let arr = []; for(i = 0; i < 10; i++) { arr.push(i); }
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (2)
Previous results
Fork
Test case name
Result
Array keys spread
for
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):
Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net! **What is being tested?** The provided JSON represents two test cases: `Array keys spread` and `for`. The benchmark aims to compare the performance of these two approaches in pushing elements onto an array. **Options compared** In this benchmark, we have two options: 1. **`Array.keys()` spread**: This method uses the spread operator (`[...]`) to create an array of keys from a range of numbers (in this case, 0 to 9). 2. **`for` loop**: This traditional approach uses a `for` loop to iterate over the range and push elements onto the array. **Pros and Cons** **Array.keys() spread:** Pros: * More concise and readable code * Less prone to errors due to automated iteration Cons: * May be slower due to the overhead of creating an array with keys * Not all browsers support this method (older versions, for example) **`for` loop:** Pros: * Widely supported across browsers and versions * Can be optimized by the compiler or engine for better performance Cons: * More verbose code, making it harder to read and maintain * Prone to errors due to manual iteration and indexing **Other considerations** In terms of optimization, modern JavaScript engines often have built-in optimizations for array push operations. However, the spread operator may still incur a slight overhead due to the creation of an intermediate array. When choosing between these two approaches, consider your specific use case: * If code readability is crucial, `Array.keys()` spread might be a better choice. * If performance is critical and you're targeting older browsers or need fine-grained control over optimizations, the `for` loop might be more suitable. **Library usage** Neither of the test cases uses any external libraries. Both approaches rely on built-in JavaScript features. **Special JS feature or syntax** There's no special JavaScript feature or syntax mentioned in these test cases. However, it's worth noting that MeasureThat.net often tests newer JavaScript features and syntax to ensure compatibility across browsers. **Alternative approaches** If you're interested in exploring alternative approaches, here are a few examples: * Using `Array.from()` instead of `Array.keys()`: This method creates an array from an iterable (in this case, the range of numbers) without using the spread operator. * Utilizing WebAssembly or other low-level optimizations: Depending on your specific use case and target browser, you might be able to achieve better performance by utilizing WebAssembly or other optimization techniques. Keep in mind that these alternatives may not be relevant for small scripts like this benchmark, but they can be useful for more complex or performance-critical applications.
Related benchmarks:
from vs spread
Splice vs Spread to insert at beginning of array
Javascript string to array mapping: Array.from() vs Spread syntax [...spread]
Array.from() vs spread []
spread vs ArrayFrom
Comments
Confirm delete:
Do you really want to delete benchmark?