Benchmark: Suffix search with String Reverse, Split vs Spread

Script Preparation code:

var str = "this is an example user supplied string of some length";
var search = "length";

Tests:

<= ES5 Split
str.split('').reverse().join('').indexOf(search.split('').reverse().join('')) === 0
>= ES6 Spread
[...str].reverse().join('').indexOf([...search].reverse().join('')) === 0

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
<= ES5 Split
>= ES6 Spread

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):

LLMs can make mistakes. Check important info.

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

**Benchmark Definition**

The benchmark is designed to compare two approaches for searching a reversed string in JavaScript:

1. Using `split` method
2. Using spread operator (`...`)

The script preparation code provides a sample user-supplied string `str` and a search term `search`.

**Approaches Compared**

There are two test cases:

1. `<= ES5 Split`: This approach uses the `split` method to reverse the strings, like this: `str.split('').reverse().join('')`
2. `>= ES6 Spread`: This approach uses the spread operator (`...`) to reverse the strings, like this: `[...str].reverse().join('')`

**Pros and Cons**

### `<= ES5 Split` (Older JavaScript Syntax)

Pros:

* Widespread support in older browsers
* Generally faster execution time due to shorter string manipulation

Cons:

* Less readable code
* May not be as efficient as newer syntax

### `>= ES6 Spread` (Newer JavaScript Syntax)

Pros:

* More readable code
* Better performance and conciseness

Cons:

* Requires support for modern browsers
* May have slight performance overhead due to additional operations

**Other Considerations**

* Both approaches require the same amount of processing power, as the reversal operation is symmetric.
* The benchmark measures the execution time of the reversed strings search.

**Library Used**

None in this specific benchmark. However, note that some JavaScript engines might use optimized libraries or built-in functions to improve performance.

**Special JS Feature/ Syntax**

There are no special features or syntax used in this benchmark.

**Alternatives**

If you wanted to test other approaches, here are a few examples:

* Using `join` and concatenation instead of splitting: `str + 'a' + (str.split('').reverse().join('') + 'b')`
* Using regular expressions: `/^(...)+$/i`

Keep in mind that these alternatives might not be as efficient or readable as the two approaches compared in this benchmark.

I hope this explanation helps!

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.61 Safari/537.36

Browser/OS: Chrome 83 on Windows

View result in a separate tab

Test name	Executions per second
<= ES5 Split	371413.9 Ops/sec
>= ES6 Spread	369556.1 Ops/sec

Related benchmarks:

Suffix search with String Reverse, Split vs Spread (version: 0)

When reversing a string, is spread or split more efficient

Comparing performance of: <= ES5 Split vs >= ES6 Spread

Created: 4 years ago by: Registered User

Jump to the latest result

<= ES5 Split

>= ES6 Spread

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):