var originalArray = [0, 1, 2, 'zero', 'one', 'two', false, true, true];
const copyArray = originalArray.slice();
const copyArray = [originalArray];
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
Slice | |
Spread |
Test name | Executions per second |
---|---|
Slice | 15301385.0 Ops/sec |
Spread | 13918969.0 Ops/sec |
I'll break down the provided benchmark definition and test cases to explain what's being tested, the options compared, their pros and cons, and other considerations.
Benchmark Definition
The Slice vs spread array
benchmark is designed to measure which approach creates a shallow copy of an array faster: using the .slice()
method or the spread operator (...
). The benchmark aims to determine if one approach is consistently faster than the other across different browsers and devices.
Options Compared
Two options are compared:
.slice()
method, which returns a new array that contains all elements from the original array, without modifying it....
), which also creates a new array by copying elements from the original array.Pros and Cons
.slice()
for large arrays, as it only copies references to the original array elements.Other Considerations
The benchmark also considers the following factors:
Library and Special JS Features
In this benchmark, no libraries are used. However, it's worth noting that the spread operator is a modern JavaScript feature introduced in ECMAScript 2015 (ES6). While most modern browsers support it, older browsers may not.
If you're interested in exploring alternative approaches or considering factors like performance and browser support for your own projects, here are some additional alternatives:
.slice()
for specific use cases.JSON.parse(JSON.stringify(originalArray))
: This approach creates a deep copy of the original array by parsing its JSON representation and then recreating it. However, this is generally slower and less efficient due to the overhead of parsing and reconstruction.Keep in mind that performance differences between these methods can vary depending on the specific use case, data size, and browser configuration. It's essential to consider your project's requirements and choose the approach that best fits your needs.