Benchmark: array[0 vs array.at(0)

Script Preparation code:

var array = [1,2,3,4,5,6];

Tests:

array[0]
const d = array[0];
array.at(0)
const z = array.at(0);

Historical Performance Data aggregated from 5 community runs

Desktop Results:

Chrome 5 runs

array.at(0)

157.0M/s

array[0]

143.1M/s

View exact numbers

✓ array.at(0): 157,022,176 ops/sec
• array[0]: 143,125,760 ops/sec

Results show median performance across all community submissions. Run this benchmark yourself to verify on your device.

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
array[0]
array.at(0)

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/133.0.0.0 Mobile Safari/537.36

Browser/OS: Chrome Mobile 133 on Android

View result in a separate tab

array[0]

42.4M/s

array.at(0)

37.4M/s

View exact numbers

Test name	Executions per second
✓ array[0]	42,370,588 Ops/sec
array.at(0)	37,407,308 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

**Benchmark Definition**

The benchmark is testing two different ways to access the first element of an array: using square brackets `[]` (e.g., `array[0]`) and using the `at()` method (e.g., `array.at(0)`).

**Options compared**

Two options are being compared:

1. **Square Brackets (`[]`)**: This is a traditional way to access an array element in JavaScript.
2. **Array.prototype.at() method**: Introduced in ECMAScript 2019, this method provides a more modern and concise way to access the first element of an array.

**Pros and Cons**

* **Square Brackets (`[]`)**:
	+ Pros: Widely supported across older browsers and environments, easy to understand.
	+ Cons: May be slower due to the need for parsing and indexing, can lead to errors if not used carefully (e.g., `array[0] === undefined`).
* **Array.prototype.at() method**:
	+ Pros: More modern and concise syntax, designed to be faster and more efficient.
	+ Cons: Requires support for ECMAScript 2019 or later, may cause issues in older browsers.

**Library usage**

There is no explicit library mentioned in the benchmark definition. However, it's worth noting that `array.at()` is a method on the `Array.prototype`, so it leverages the built-in JavaScript array functionality.

**Special JS feature/syntax**

The `at()` method uses the **Symbol.atSymbol** property (e.g., ` Symbol('at')`), which is a new syntax introduced in ECMAScript 2019. This property allows the creation of unique symbol keys, including `at`.

**Other alternatives**

If you wanted to test other ways of accessing array elements, you could consider adding more benchmark definitions with different approaches, such as:

* Using `array[0]` instead of `array.at(0)`
* Using a custom function or helper library
* Testing indexing arithmetic (e.g., `array[3]`)
* Testing slicing syntax (e.g., `array.slice(1, 2)`)

These additional test cases would help to further illustrate the performance differences between various methods and libraries in JavaScript.

array[0 vs array.at(0) (version: 0)

Comparing performance of: `array[0] vs array.at(0)`

Created: one year ago by: Guest

Go to the latest result

array[0]

array.at(0)

Historical Performance Data aggregated from 5 community runs

Desktop Results:

Chrome 5 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

array[0 vs array.at(0) (version: 0)

Comparing performance of: array[0] vs array.at(0)

Created: one year ago by: Guest

Go to the latest result

array[0]

array.at(0)

Historical Performance Data aggregated from 5 community runs

Desktop Results:

Chrome 5 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

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Comparing performance of: `array[0] vs array.at(0)`