Benchmark: indexOf: compare to -1 or use ~

Script Preparation code:

var constants = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'.split('');
var findable = 'A';
var unfindable = '0';

Tests:

Compare to -1
if (constants.indexOf(findable) !== -1) { var A = true; } if (constants.indexOf(unfindable) !== -1) { var O = true; }
Use tilde
if (~constants.indexOf(findable)) { var A = true; } if (~constants.indexOf(unfindable)) { var O = true; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Compare to -1
Use tilde

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested, compared, and their pros and cons.

**Benchmark Definition**

The benchmark is designed to compare two approaches for checking if an element exists in an array using the `indexOf()` method:

1. Comparing to -1 (using `indexOf(findable) !== -1`)
2. Using the tilde operator (`~constants.indexOf(findable)`)

**Script Preparation Code**

The script preparation code defines two variables:

* `constants`: an array of all lowercase and uppercase letters
* `findable`: a string containing the letter "A" (in lowercase)
* `unfindable`: a string containing the number "0"

These variables are used to create an array with 52 elements, making it suitable for performance testing.

**Html Preparation Code**

There is no HTML preparation code provided, which means that the benchmark does not include any additional setup or rendering of web pages.

**Individual Test Cases**

The benchmark consists of two test cases:

1. "Compare to -1": This test case uses the traditional approach with `indexOf(findable) !== -1` to check if the element exists in the array.
2. "Use tilde": This test case uses the tilde operator (`~constants.indexOf(findable)`) to achieve the same result.

**Libraries and Features**

There are no external libraries used in this benchmark, and there is no special JavaScript feature or syntax being tested.

**Pros and Cons of Each Approach**

1. **Comparing to -1**
	* Pros:
		+ Wide support across browsers
		+ Easy to understand and implement
	* Cons:
		+ Can be slower than alternative approaches for large arrays
2. **Using the tilde operator (`~constants.indexOf(findable)`)**
	* Pros:
		+ Can be faster than traditional `indexOf()` for large arrays
		+ Does not modify the original array
	* Cons:
		+ Requires a modern browser that supports the tilde operator
		+ May have different performance characteristics across browsers

**Other Considerations**

When choosing between these two approaches, consider the following factors:

* Performance: If you're working with large arrays or need to optimize for speed, the tilde operator might be a better choice.
* Compatibility: If you need to support older browsers, stick with the traditional approach using `indexOf()`.
* Code readability and maintainability: The traditional approach is often easier to understand and modify.

**Alternative Approaches**

Some other approaches for checking if an element exists in an array include:

1. Using a loop (`for (var i = 0; i < constants.length; i++) { ... }`)
2. Using the `includes()` method (available in modern browsers)
3. Using a custom implementation with bitwise operations

These alternatives may offer different trade-offs in terms of performance, compatibility, and code readability.

I hope this explanation helps! Let me know if you have any further questions or need clarification on any of these points.

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.114 YaBrowser/20.11.1.81 Yowser/2.5 Safari/537.36

Browser/OS: Yandex Browser 20 on Windows

View result in a separate tab

Test name	Executions per second
Compare to -1	1430872.2 Ops/sec
Use tilde	1420958.5 Ops/sec

Related benchmarks:

indexOf: compare to -1 or use ~ (version: 0)

Comparing performance of: Compare to -1 vs Use tilde

Created: 7 years ago by: Guest

Jump to the latest result

Compare to -1

Use tilde

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):