var baseArray = []for (var i = 0; i < 50; i++) { baseArray.push((Math.floor(Math.random() * Math.floor(1000000))).toString(16)) }var other = baseArray.slice();var other = [baseArray];var other = baseArray.slice(0);--enable-precise-memory-info flag.
| Test case name | Result |
|---|---|
| Array.prototype.slice() | |
| spread operator | |
| Array.prototype.slice(0) |
| Test name | Executions per second |
|---|---|
| Array.prototype.slice() | 22088500.0 Ops/sec |
| spread operator | 3264545.5 Ops/sec |
| Array.prototype.slice(0) | 22137490.0 Ops/sec |
Let's break down the provided benchmark definition and test cases.
What is tested on the provided JSON?
The provided JSON represents a JavaScript microbenchmark that compares three different approaches for creating a subset of an array:
Array.prototype.slice(): This method creates a shallow copy of a portion of an array....): This operator was introduced in ES6 and allows for the creation of new arrays from existing ones by spreading elements or properties into a new array.Array.prototype.slice(0): This method is similar to slice(), but it only returns the subset of elements starting from the beginning of the array.Options compared
The benchmark compares these three approaches:
Array.prototype.slice():...):Array.prototype.slice(0):slice(), but with an additional parameter that can be useful for certain use cases.Library usage
None of the test cases explicitly use a library. However, it's worth noting that Array.prototype.slice() and Array.prototype.slice(0) are built-in methods of the Array prototype in JavaScript.
Special JS feature or syntax
The benchmark uses ES6 syntax for the spread operator (...), which was introduced in 2015. If you're using an older version of JavaScript, this syntax may not be supported.
Other alternatives
In addition to these three approaches, there are other ways to create a subset of an array:
Array.prototype.map() and slice(): map() can be used to create a new array with the desired subset of elements, followed by slice() to extract only those elements.Array.prototype.filter() and slice(): Similar to the previous approach, using filter() to create a new array with the desired elements, followed by slice() to extract those elements.While these alternatives are possible, they may not be as concise or efficient as the three approaches being compared in this benchmark.
