Benchmark: get element from array = [0] vs pop()

Script Preparation code:

var x = [1,2,3]

Tests:

var a = x[0]
var a = x[0]
var a = x.pop()
var a = x.pop()

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
var a = x[0]
var a = x.pop()

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/102.0.0.0 Safari/537.36

Browser/OS: Chrome 102 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
var a = x[0]	15647807.0 Ops/sec
var a = x.pop()	15157385.0 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 and the pros and cons of different approaches.

**What is being tested?**

The test measures two ways to access an element at index 0 from an array `x`:

1. Using bracket notation (`x[0]`)
2. Using the `pop()` method

**Options comparison:**

Here's a brief overview of each approach:

* **Bracket Notation (`x[0]`)**:
	+ Pros:
		- Fast and efficient, as it directly accesses the array element.
		- Simple and widely supported in most browsers.
	+ Cons:
		- May throw an error if `x` is not an array or if the index is out of bounds.
* **Pop() Method (`x.pop()`)**:
	+ Pros:
		- Removes the last element from the array, which can be useful for certain use cases.
		- Does not require explicit indexing.
	+ Cons:
		- May be slower than bracket notation due to additional overhead.
		- Returns `undefined` instead of throwing an error if the index is out of bounds.

**Other considerations:**

In addition to these two approaches, other factors that might affect performance include:

* Array size and structure (e.g., sparse arrays, large arrays)
* Browser and JavaScript engine optimizations
* Context in which the array is used (e.g., for loops, event listeners)

**Library usage:**

There are no libraries mentioned in the benchmark code. However, if a library like `Lodash` or `Underscore.js` were used to access elements of an array, it would likely use bracket notation or similar techniques.

**Special JavaScript feature or syntax:**

None are mentioned in this specific benchmark.

**Benchmark preparation code and individual test cases:**

The script preparation code creates an array `x` with a single element `[1,2,3]`. The individual test cases access the first element of the array using either bracket notation (`x[0]`) or the `pop()` method. These test cases are likely designed to measure the performance difference between these two approaches.

**Latest benchmark result:**

The results show that Chrome 102 on a desktop device with Mac OS X 10.15.7 executed both test cases:

* Bracket notation (`x[0]`): approximately 15647807 executions per second
* `pop()` method: approximately 15157385 executions per second

In this specific case, bracket notation seems to be slightly faster than the `pop()` method. However, it's essential to note that these results may vary depending on the specific use case and environment.

Related benchmarks:

get element from array = [0] vs pop() (version: 0)

Comparing performance of: var a = x[0] vs var a = x.pop()

Created: 2 years ago by: Guest

Jump to the latest result

var a = x[0]

var a = x.pop()

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):