var limit = 1000var a = new Array(limit).fill(limit);var b = a.slice();b.unshift(limit);var b = [ limit, a ];--enable-precise-memory-info flag.
| Test case name | Result |
|---|---|
| Array.prototype.slice | |
| spread operator |
| Test name | Executions per second |
|---|---|
| Array.prototype.slice | 1045389.1 Ops/sec |
| spread operator | 191126.2 Ops/sec |
Let's break down the benchmark test case.
What is being tested?
The benchmark is comparing two approaches to create a new array by copying an existing array:
Array.prototype.slice()...)Options compared:
The two options are compared in terms of performance, which is the primary metric being measured.
Pros and Cons of each approach:
Array.prototype.slice():...):slice() for large arrays, as it only creates a single array object.Library/Utility:
There is no specific library or utility being used in this benchmark. The focus is solely on comparing the two JavaScript operators.
Special JS feature/syntax:
The ES6 spread operator (...) is a new syntax introduced in ECMAScript 2015 (ES6). It allows for creating a new array by copying elements from an existing array, without the need for Array.prototype.slice() or other methods.
Other alternatives:
If you wanted to use alternative approaches to create a new array, some options could be:
Array.prototype.concat(): This method creates a new array by concatenating multiple arrays. However, it may not be as efficient as slice() for very large arrays.Array.from(): This method creates a new array from an iterable or an array-like object. It may be more suitable than slice() for creating arrays with specific elements.In general, when working with arrays in JavaScript, the choice of approach depends on the specific use case and performance requirements.
Keep in mind that this benchmark is focused on comparing two specific approaches within the JavaScript language, rather than exploring alternative programming paradigms or languages.
