Benchmark: pop() and push() vs. splice()

Tests:

pop() and push()
var arr = ['1', '2', '3']; arr.pop(); arr.push("4");
slice()
var arr = ['1', '2', '3']; arr.splice(arr.length - 1, 1, "4");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
pop() and push()
slice()

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:109.0) Gecko/20100101 Firefox/113.0

Browser/OS: Firefox 113 on Windows

View result in a separate tab

Test name	Executions per second
pop() and push()	57792952.0 Ops/sec
slice()	14241973.0 Ops/sec

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

LLMs can make mistakes. Check important info.

I'd be happy to explain what's being tested in the provided benchmark.

The benchmark is comparing two approaches for modifying an array: `pop()` and `push()`, versus `splice()`. The test cases are designed to measure which approach is faster, more efficient, or both.

Let's break down each option:

**1. `pop()` and `push()`**

This approach involves removing the last element from the array using `arr.pop()` and then appending a new element using `arr.push("4")`. The pros of this approach are:

* It's often considered more intuitive and easier to read, as it follows a common pattern in programming.
* It may be faster for small arrays or arrays with few elements.

However, the cons are:

* For larger arrays, `push()` can lead to inefficient use of memory, especially if there are many allocations and deallocations. This is because `push()` creates a new array with the updated elements, which can be slow.
* The overhead of removing an element from the end of the array using `pop()` can also impact performance.

**2. `splice()`**

This approach involves modifying the original array by removing the last element and replacing it with a new one using `arr.splice(arr.length - 1, 1, "4")`. The pros of this approach are:

* It's more memory-efficient than `push()`, as it modifies the existing array without creating a new one.
* For larger arrays, `splice()` can be faster because it avoids unnecessary allocations and deallocations.

However, the cons are:

* It may require more manual manipulation of indices and array bounds, making it harder to read and understand for some developers.
* The order of elements in the original array is affected, which might not be desirable in all situations.

The benchmark result shows that `splice()` is faster than `pop()` and `push()`, indicating that modifying an array using this approach may be more efficient for larger arrays or high-performance scenarios. However, it's essential to consider the trade-offs between readability, maintainability, and performance when choosing between these approaches.

As for libraries used in the benchmark, none are explicitly mentioned in the provided code snippets. However, `slice()` is a built-in JavaScript function that can be used to create a shallow copy of an array. If a library were used, it might be something like Lodash or Ramda, but without more context, it's difficult to say.

There aren't any special JavaScript features or syntax used in these test cases, so no additional explanations are needed.

Other alternatives for modifying arrays include:

* Using `unshift()` and `concat()` to add elements to the beginning of an array
* Using `indexOf()`, `slice()`, and `push()` to insert an element at a specific index
* Using `map()` and `reduce()` to transform arrays

Keep in mind that the choice of approach depends on the specific requirements and constraints of your project, such as performance, memory usage, and readability.

Related benchmarks:

pop() and push() vs. splice() (version: 0)

Comparing performance of: pop() and push() vs slice()

Created: 3 years ago by: Guest

Jump to the latest result

pop() and push()

slice()

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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