Benchmark: String.indexOf vs Array.indexOf

Script Preparation code:

var LENGTH = 1_000_000;

var str = new Array(LENGTH).fill('z', 0, LENGTH).join('');
var arr = new Array(LENGTH).fill('z', 0, LENGTH - 1);

Tests:

String.indexOf
str.indexOf('a')
Array.indexOf
arr.indexOf('a')

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
String.indexOf
Array.indexOf

Fastest: N/A

Slowest: N/A

Latest run results:

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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's being tested.

**Benchmark Definition**

The benchmark definition specifies two tests:

1. `str.indexOf('a')`: This test measures the performance of the `indexOf` method on a string object, specifically looking for the character `'a'`.
2. `arr.indexOf('a')`: This test measures the performance of the `indexOf` method on an array object, also searching for the character `'a'`.

**Options Compared**

The two tests compare the performance of different implementations of the `indexOf` method:

1. **String** (`str.indexOf('a')`):
	* In JavaScript, strings have their own `indexOf` method that searches for a specified value in the string.
2. **Array** (`arr.indexOf('a')`):
	* Arrays also have an `indexOf` method, but it's not directly comparable to the string implementation.

**Pros and Cons**

1. **String**:
	+ Pros: Native JavaScript method, optimized for strings.
	+ Cons: May be slower than array implementation due to additional checks (e.g., checking if the input is a string).
2. **Array**:
	+ Pros: Can be faster than string implementation, as it's implemented in native code and doesn't require additional checks.
	+ Cons: Requires a valid index into the array, which might not always exist.

**Library/Technology**

There isn't a specific library mentioned in the benchmark definition. However, both `String` and `Array` are built-in JavaScript objects.

**Special JS Features/Syntax**

None of the test cases explicitly use special JavaScript features or syntax (e.g., ES6 modules, async/await).

**Other Alternatives**

To measure the performance difference between string and array implementations, alternative benchmarks could be created:

* Testing both string and array implementations on different data types (e.g., numbers, booleans).
* Measuring performance with varying input sizes or distributions.
* Using other JavaScript engines or browsers to compare results.

Keep in mind that the specific implementation details of `String` and `Array` may vary across browsers, so it's essential to test with multiple environments if possible.

Related benchmarks:

String.indexOf vs Array.indexOf (version: 0)

Comparing performance of: String.indexOf vs Array.indexOf

Created: 3 years ago by: Guest

Jump to the latest result

String.indexOf

Array.indexOf

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):