var params = [ "hello", true, 7 ];
var other = [ 1, 2 ].slice();
var params = [ "hello", true, 7 ]
var other = [ params ]
var params = [ "hello", true, 7 ]
var other = Array.from(params);
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
Array.prototype.slice | |
spread operator | |
Array.from |
Test name | Executions per second |
---|---|
Array.prototype.slice | 115410008.0 Ops/sec |
spread operator | 68738480.0 Ops/sec |
Array.from | 6116484.5 Ops/sec |
Let's break down the provided benchmark and its options.
Benchmark Overview
The benchmark compares three ways to create an array copy: Array.prototype.slice()
, the spread operator (...
), and Array.from()
.
Options Compared
Array.prototype.slice()
: This method creates a shallow copy of a portion of an existing array....
): This operator creates a new array by spreading elements from an iterable (such as an array).Array.from()
: This method creates a new array from an iterable (such as an array or string).Pros and Cons
Array.prototype.slice()
:...
):Array.from()
:slice()
, and may have performance issues on older browsers or platforms.Library Usage
None of the options explicitly use a library in this benchmark. However, if we consider external dependencies (e.g., browser-specific APIs), we might see some variations in performance due to differences in implementation across browsers.
Special JS Features or Syntax
The spread operator (...
) is a relatively new feature introduced in ECMAScript 2015. It's an example of a modern JavaScript syntax that can have different performance characteristics compared to older methods like slice()
.
Benchmark Preparation Code and HTML Preparation Code
These are not explicitly provided, but it's implied that the test cases assume some basic setup for running the benchmark, such as creating an array with sample data (params
) and then creating a copy using each of the three options.
Alternatives to Consider
Array.prototype.slice.call()
).concat()
, could potentially be used as alternatives.Keep in mind that this is a general analysis, and the actual performance differences between these options may vary depending on the specific use case, data type, and target platform.