Benchmark: Array split vs string slice

Script Preparation code:

var s1 = "1610238974228/hellothere";

Tests:

string.split
var n1 = s1.split("/")[0];
string slice
var n1 = s1.slice(0,13);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
string.split
string slice

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/136.0.0.0 Safari/537.36

Browser/OS: Chrome 136 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
string.split	46889188.0 Ops/sec
string slice	187695216.0 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 comparing two approaches to split or slice a string in JavaScript: `split()` and `slice()`. The benchmark consists of a single script preparation code that defines a string variable `s1` containing a URL, and then uses both `split()` and `slice()` to extract the first part of the URL.

**Test Cases**

There are two individual test cases:

1. `"string.split"`: This test case uses the `split()` method to split the string `s1` at the `/` character and extracts the first part using `[0]`.
2. `"string slice"`: This test case uses the `slice()` method to extract the first 13 characters of the string `s1`.

**Options Compared**

The benchmark is comparing the performance of:

* `split()` with a regular expression (`/\/`)
* `slice()` with a specified start index (0) and length (13)

**Pros and Cons**

* **`split()`**: Pros:
	+ Can split strings at any character or substring.
	+ Returns an array of substrings, which can be useful in certain scenarios.
Cons:
	+ Creates a new array object, which can be memory-intensive for large strings.
	+ May have slower performance due to regular expression processing.
* **`slice()`**: Pros:
	+ Returns a new string with the specified characters, which is more memory-efficient than `split()`.
	+ Can specify an exact length, which can be faster for shorter substrings.
Cons:
	+ Only works for strings and not for arrays or other data types.
	+ May have slower performance for very long strings due to indexing.

**Library/Functionality Used**

There is no library used in this benchmark. Both `split()` and `slice()` are built-in JavaScript functions.

**Special JS Feature/Syntax**

There is no special JavaScript feature or syntax used in this benchmark. The code only uses standard JavaScript syntax and built-in functions.

**Other Considerations**

When choosing between `split()` and `slice()`, consider the following:

* If you need to split a string at any character or substring, use `split()`.
* If you need to extract a specific part of a string with an exact length, use `slice()`.
* If memory efficiency is crucial, use `slice()`.
* If performance is critical for very long strings, consider using `split()` with a regular expression.

**Other Alternatives**

If you're looking for alternative approaches to split or slice strings in JavaScript, consider:

* Using `indexOf()` and `substr()` (or `substring()`) instead of `slice()`.
* Using a library like Lodash's `chunk()` function.
* Using a regex-based approach with `replace()`.

Keep in mind that these alternatives may have different performance characteristics and use cases compared to `split()` and `slice()`.

Related benchmarks:

Array split vs string slice (version: 0)

Comparing performance of: string.split vs string slice

Created: 5 years ago by: Guest

Jump to the latest result

string.split

string slice

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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