Benchmark: Array.prototype.slice vs spread operator vs Array.prototype.from

Tests:

Array.prototype.slice
var params = [ "hello", true, 7 ]; var other = [ 1, 2 ].slice();
spread operator
var params = [ "hello", true, 7 ] var other = [ ...params ]
Array.prototype.from
var params = [ "hello", true, 7 ] var other = Array.from(params.values())

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Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.prototype.slice
spread operator
Array.prototype.from

Fastest: N/A

Slowest: N/A

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Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

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Let's break down the provided JSON and explain what is being tested, compared options, pros and cons of each approach, and other considerations.

**Benchmark Definition**

The benchmark defines three test cases to compare the performance of:

1. `Array.prototype.slice()`
2. The new ES6 spread operator (`[ ...params ]`)
3. `Array.prototype.from()` with a `values()` method

These test cases aim to measure the execution time and speed of each approach when creating a shallow copy of an array containing different types of values (strings, booleans, numbers).

**Test Case 1: Array.prototype.slice()**

The benchmark starts by defining a test case for `Array.prototype.slice()`. In this test, an array `params` is created with three elements: "hello", `true`, and `7`. Then, another array `other` is created using the `slice()` method. The test aims to measure how long it takes to create this copy.

**Test Case 2: Spread Operator**

The second test case uses the new ES6 spread operator (`[ ...params ]`) to create a shallow copy of the `params` array. This test measures the execution time of creating an array with elements extracted from the original `params` array using the spread operator.

**Test Case 3: Array.prototype.from()**

The third and final test case uses `Array.prototype.from()` with a `values()` method to create a shallow copy of the `params` array. This approach creates an iterator that yields values from the original array, which are then used to construct a new array. The benchmark measures how long it takes to execute this process.

**Comparison and Considerations**

When choosing between these approaches, consider the following:

* **Performance:** The spread operator (`[ ...params ]`) is generally faster than `Array.prototype.slice()`, as it creates a new array with references to the original elements. On the other hand, `Array.prototype.from()` can be slower due to its iterative nature and the need to create an iterator.
* **Memory Usage:** All three approaches create a shallow copy of the original array, but the spread operator uses less memory since it only stores references to the original elements.
* **Readability and Maintainability:** The spread operator can make code more readable by clearly expressing the intent of creating a new array with extracted values. `Array.prototype.slice()` can be more concise, but its usage might not be immediately clear to developers unfamiliar with this method.

**Libraries and Special Features**

There is no specific library used in these test cases. However, it's worth noting that `Array.from()` relies on the built-in `values()` method of arrays, which was introduced in ECMAScript 2017 (ES7).

No special JavaScript features or syntax are used beyond the standard ES6 spread operator and `Array.prototype.slice()`.

Related benchmarks:

Array.prototype.slice vs spread operator vs Array.prototype.from (version: 0)

Compare the new ES6 spread operator with the traditional slice() method

Comparing performance of: Array.prototype.slice vs spread operator vs Array.prototype.from

Created: 4 years ago by: Guest

Jump to the latest result

Array.prototype.slice

spread operator

Array.prototype.from

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):