Toggle navigation
MeasureThat.net
Create a benchmark
Tools
Feedback
FAQ
Register
Log In
Array.prototype.concat vs spread operator - small arrays
(version: 0)
Compare the new ES6 spread operator with the traditional concat() method
Comparing performance of:
Array.prototype.concat vs spread operator
Created:
6 years ago
by:
Registered User
Jump to the latest result
Script Preparation code:
var arr1 = []; var arr2 = []; for(let i = 0; i < 10; i++) { arr1.push(i); arr2.push(i); }
Tests:
Array.prototype.concat
[].concat(arr1, arr2);
spread operator
[...arr1, ...arr2];
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (2)
Previous results
Fork
Test case name
Result
Array.prototype.concat
spread operator
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 break down the provided JSON data and explain what's being tested. **Benchmark Definition** The benchmark definition compares two approaches for merging arrays: `Array.prototype.concat` (traditional method) and the new ES6 spread operator (`[...]`). The test is designed to measure the performance of these two methods on small arrays. **Script Preparation Code** The script preparation code creates two empty arrays, `arr1` and `arr2`, and then populates them with 10 elements using a `for` loop. This ensures that both arrays have an equal number of elements when merged. **Html Preparation Code** There is no HTML preparation code specified, which means the benchmark is focused solely on the JavaScript implementation. **Individual Test Cases** The benchmark consists of two test cases: 1. **Array.prototype.concat**: This test case uses the traditional `concat` method to merge the two arrays. 2. **spread operator**: This test case uses the new ES6 spread operator (`[...]`) to merge the two arrays. Now, let's discuss the pros and cons of each approach: **Array.prototype.concat** Pros: * Wide browser support: `concat` has been part of the JavaScript specification since 1999. * Simple implementation: The method is straightforward to understand and implement. Cons: * Performance overhead: `concat` creates a new array object, which can lead to performance issues for large arrays. **Spread Operator (New ES6 Syntax)** Pros: * Concise syntax: The spread operator is a more compact way of merging arrays. * Efficient implementation: Modern JavaScript engines have optimized implementations of the spread operator, making it faster than `concat`. Cons: * Limited browser support: While the spread operator has been part of the JavaScript specification since 2015, older browsers may not have implemented it. **Library/Function Usage** In this benchmark, there is no external library or function being used. The test cases only rely on built-in JavaScript methods (`Array.prototype.concat` and the spread operator). **Special JS Feature/Syntax** This benchmark does not use any special JavaScript features or syntax beyond what's been introduced in the latest ES6 specification (2015). **Alternatives** Other alternatives for merging arrays include: * Using `Array.prototype.push()` to append elements to one array, then creating a new array with the desired number of elements. * Utilizing a library like Lodash, which provides a `concat` function that can be used instead of the built-in method. Keep in mind that these alternatives may have different performance characteristics and may not be as concise or readable as the spread operator.
Related benchmarks:
concat 2 arrays: Array.prototype.concat vs spread operator
Array.prototype.concat vs spread operator - larger arrays
Array concat vs spread operator vs push for single values
Array.prototype.concat vs spread operator (new try)
Comments
Confirm delete:
Do you really want to delete benchmark?