var arr = ['1','2','3','4','5','6','7','8']
[arr]
arr.slice()
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
Copy via spread operator | |
Copy via slice |
Test name | Executions per second |
---|---|
Copy via spread operator | 5026856.5 Ops/sec |
Copy via slice | 10054126.0 Ops/sec |
Let's break down the benchmark definition and test cases to understand what is being tested.
Benchmark Definition:
The provided JSON represents a JavaScript microbenchmark that compares two approaches to create a copy of an array:
[...arr]
)slice()
method (arr.slice()
)This benchmark aims to measure which approach is faster and more efficient in creating an array copy.
Options Compared:
Two options are compared:
a. Copy via spread operator: This method uses the spread operator ([...]
) to create a new array by iterating over each element of the original array.
b. Copy via slice: This method uses the slice()
method to create a shallow copy of the original array.
Pros and Cons:
slice()
method and handling edge cases like empty arrays.Library Usage:
None of the test cases use any external libraries. The benchmark only relies on built-in JavaScript features.
Special JS Features/Syntax:
The test case uses the spread operator ([...arr]
) which is a modern JavaScript feature introduced in ECMAScript 2015 (ES6). This syntax allows for creating new arrays from existing iterables, making it more concise and expressive. The slice()
method is also a built-in JavaScript function.
Other Alternatives:
For array copying, other alternatives include:
Array.prototype.copyWithin()
method (introduced in ECMAScript 2019)Array.from()
constructor with an iterablelodash
library's cloneDeep()
functionHowever, these alternatives may not be as efficient or concise as the spread operator and slice methods used in this benchmark.
I hope this explanation helps software engineers understand what is being tested in the MeasureThat.net benchmark!