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from vs spread
(version: 0)
Comparing performance of:
from vs spread
Created:
6 years ago
by:
Guest
Jump to the latest result
Script Preparation code:
var n = 100000
Tests:
from
Array.from(Array(n).keys())
spread
[...Array(n).keys()]
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (2)
Previous results
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Test case name
Result
from
spread
Fastest:
N/A
Slowest:
N/A
Latest run results:
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Autogenerated LLM Summary
(model
llama3.2:3b
, generated one year ago):
Let's break down what's being tested in the provided benchmark. **What is being tested?** The benchmark is comparing two approaches to create an array of numbers from 0 to n-1: `Array.from(Array(n).keys())` and `[...Array(n).keys()]`. **Options compared** There are two options being compared: 1. **`Array.from(Array(n).keys())`**: This method creates a new array by mapping over the keys of an existing array, which is created using `Array(n)`. The `keys()` method returns an array containing consecutive integers from 0 to n-1. 2. **`[...Array(n).keys()]`**: This syntax uses the spread operator (`...`) to create a new array by spreading the elements of an array. The `[...Array(n).keys()]` expression creates a new array with consecutive integers from 0 to n-1. **Pros and Cons** * **`Array.from(Array(n).keys())`**: + Pros: Can be more readable, especially for those familiar with ES6 syntax. + Cons: May require additional imports (`import { from } from 'es6-array';`) or may not work in older browsers that don't support `from`. * **`[...Array(n).keys()]`**: + Pros: More concise and readable, especially for those familiar with spread operators. + Cons: May be less explicit about what's being done (as it relies on the spread operator). Other considerations: * Both methods are generally efficient and have similar performance characteristics. However, there might be subtle differences due to various factors like browser implementation or JavaScript engine optimizations. **Libraries and special JS features** There are no specific libraries mentioned in the benchmark definition or test cases. If we were to add special JavaScript features, it would likely depend on what's being tested. For example: * **`const` and `let` declarations**: Are these used as part of the script preparation code? * **Arrow functions**: Are they used anywhere in the test cases? Since neither is mentioned here, I'll leave it out. **Other alternatives** To create an array of consecutive integers from 0 to n-1, other approaches could be: * Using a `for` loop: `var arr = []; for (var i = 0; i < n; i++) { arr.push(i); }` * Using `Array.from()` with an array of numbers: `var arr = Array.from(new Array(n).fill(0));` However, these alternatives are generally less concise and readable than the two options being compared in this benchmark. I hope this explanation helps!
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