Benchmark: endsWith vs index

Script Preparation code:

var a="this is a very long string"

Tests:

endsWith multiple
const b = a.endsWith("ring")
index multiple
const b= a[a.length-4]==='r'&&a[a.length-3]==='i'&&a[a.length-2]==='n'&&a[a.length-1]==='g'
endsWith single
const b = a.endsWith("g")
index single
const b= a[a.length-1]==='g'

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
endsWith multiple
index multiple
endsWith single
index single

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36

Browser/OS: Chrome 135 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
endsWith multiple	67719304.0 Ops/sec
index multiple	82183712.0 Ops/sec
endsWith single	102641416.0 Ops/sec
index single	111797072.0 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 provided benchmark and explain what's being tested.

**Benchmark Overview**

The benchmark is designed to compare the performance of two approaches for checking if a string ends with a specific suffix: `endsWith` (a built-in JavaScript method) versus using an index-based approach (`index`).

**Options Compared**

Two options are compared:

1. **endsWith**: A built-in JavaScript method that uses a regular expression under the hood to check if a string ends with a specified value.
2. **Index-based approach (`index`)**: This approach involves accessing specific indices of the string to check for the desired suffix.

**Pros and Cons**

**endsWith**

Pros:

* Concise and readable code
* Efficient implementation (uses regular expressions, which are optimized for performance)

Cons:

* May be slower than the index-based approach due to the overhead of regular expression processing

**Index-based approach (`index`)**

Pros:

* Can be faster than `endsWith` since it avoids the overhead of regular expression processing
* More explicit and potentially easier to understand for those familiar with string indexing

Cons:

* Requires accessing specific indices of the string, which can lead to slower performance due to additional computations
* May require more memory allocations and deallocations compared to `endsWith`

**Considerations**

When choosing between these approaches, consider the trade-off between conciseness, readability, and performance. If you prioritize ease of understanding and a concise implementation, `endsWith` might be the better choice. However, if you need optimal performance and are willing to invest in more explicit indexing code, the index-based approach could be a better option.

**Libraries Used**

The benchmark uses JavaScript's built-in `endsWith` method, which is part of the ECMAScript standard. No external libraries are required.

**Special JS Features or Syntax**

None of the test cases explicitly use any special JavaScript features or syntax beyond what's covered in the ECMAScript standard.

**Other Alternatives**

If you'd like to explore alternative approaches, consider:

* Using a library like `string.prototype.endsWith` with a caching mechanism to improve performance
* Implementing a custom string searching algorithm using bitwise operations (e.g., `str.substring(str.length - n) == suffix`)
* Using a more advanced string manipulation library or framework that provides optimized string matching functions

Keep in mind that these alternatives might introduce additional complexity, trade-offs, or dependencies not present in the original benchmark.

Related benchmarks:

endsWith vs index (version: 0)

Checks endsWith vs index

Comparing performance of: endsWith multiple vs index multiple vs endsWith single vs index single

Created: 2 years ago by: Registered User

Jump to the latest result

endsWith multiple

index multiple

endsWith single

index single

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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