Benchmark: Last element slice vs pop

Script Preparation code:

var arr =[0, 1, 2, 3, 4, 5, 6, 7, 8, 9];

Tests:

Slice
arr.slice(-1)
Pop
arr.pop()

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Slice
Pop

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:130.0) Gecko/20100101 Firefox/130.0

Browser/OS: Firefox 130 on Windows

View result in a separate tab

Test name	Executions per second
Slice	86993896.0 Ops/sec
Pop	474924000.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what's being tested.

**Benchmark Overview**

The benchmark compares two approaches to accessing the last element of an array in JavaScript: using the `slice` method with a negative index, and using the `pop` method.

**Options Compared**

There are two options compared:

1. **Slice**: Using `arr.slice(-1)` to access the last element of the array.
2. **Pop**: Using `arr.pop()` to remove and return the last element of the array.

**Pros and Cons of Each Approach**

1. **Slice:**
	* Pros:
		+ More explicit and readable way to access the last element.
		+ Does not modify the original array.
	* Cons:
		+ May be slower than `pop` due to the overhead of creating a new slice object.
2. **Pop:**
	* Pros:
		+ Faster than `slice`, as it only needs to remove and return one element.
	* Cons:
		+ Modifies the original array, which may not be desirable in some cases.
		+ Less explicit and readable, as it relies on the implementation of `pop` to handle errors.

**Library Usage**

In this benchmark, no specific library is used beyond what's part of the JavaScript standard library. The `slice` method is a built-in array method that creates a new slice object from the original array.

**Special JS Feature or Syntax**

There are no special features or syntaxes being tested in this benchmark. Both approaches use plain JavaScript and standard methods.

**Other Considerations**

This benchmark focuses on the performance difference between two common ways to access the last element of an array. It's likely that the results will be relevant to developers who need to optimize performance-critical code involving arrays.

**Alternative Approaches**

If you're looking for alternative approaches, here are a few:

1. **Array.prototype.at()**: Introduced in ECMAScript 2019, this method allows you to access an element at a specific index without creating a new slice object.
2. **Array.prototype.get()**: Some modern browsers support the `get()` method on arrays, which can be used to access elements without modifying the original array.

Keep in mind that these alternative approaches may have their own trade-offs and limitations, but they offer different solutions to accessing last elements of arrays.

In conclusion, this benchmark provides a simple yet informative way to compare the performance of two common ways to access the last element of an array: using `slice` or `pop`.

Related benchmarks:

Last element slice vs pop (version: 0)

Comparing performance of: Slice vs Pop

Created: one year ago by: Guest

Jump to the latest result

Slice

Pop

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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