Benchmark: str split vs spread

Script Preparation code:

var str = "hello";

Tests:

split
var other = str.split('');
spread
var other = [...str];

Historical Performance Data aggregated from 23 community runs

Desktop Results:

Chrome 18 runs

split

27.2M/s

spread

21.9M/s

Fastest: split (1.2x faster)

View exact numbers

✓ split: 27,225,082 ops/sec
• spread: 21,917,920 ops/sec

Mobile Results:

Chrome 5 runs

spread

19.0M/s

split

11.5M/s

Fastest: spread (1.6x faster)

View exact numbers

✓ spread: 18,968,510 ops/sec
• split: 11,534,712 ops/sec

Results show median performance across all community submissions. Run this benchmark yourself to verify on your device.

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
split
spread

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 9 months ago)

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Mobile Safari/537.36

Browser/OS: Chrome Mobile 142 on Android

View result in a separate tab

split

34.3M/s

spread

20.0M/s

View exact numbers

Test name	Executions per second
✓ split	34,293,656 Ops/sec
spread	19,996,584 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 definition and test cases to understand what's being tested.

**Benchmark Definition**

The benchmark is called "str split vs spread" and it's defined as follows:
```
var str = "hello";
```
This code creates a string variable `str` with the value `"hello"`.

**Test Cases**

There are two individual test cases:

1. **Split**: The first test case uses the `split()` method to split the string into an array.
```
var other = str.split('');
```
The `split()` method takes an optional argument, which is the separator used to split the string. In this case, no separator is provided, so it splits the string at each character.

2. **Spread**: The second test case uses the spread operator (`...`) to create a new array from the string.
```
var other = [...str];
```
The spread operator creates a new array by iterating over the elements of the original string and adding them as separate elements to the new array.

**Library**

There is no explicit library used in these test cases. However, it's worth noting that some browsers might use optimized implementations of these methods that rely on underlying libraries or engine-specific optimizations.

**Special JS Feature/Syntax**

The spread operator (`...`) is a relatively recent feature introduced in ECMAScript 2015 (ES6). It allows you to create a new array by iterating over the elements of an existing value, such as an array, object, or string. In this case, it's used to create a new array from the string `str`.

**Pros and Cons**

Here are some pros and cons of each approach:

* **Split() method**: Pros:
	+ Widely supported by most browsers
	+ Can be used with arbitrary separators (not just spaces or commas)
Cons:
	+ May be slower for very large strings due to the overhead of creating an array
	+ Can be less readable in some cases, as it returns an empty string if no separator is provided
* **Spread operator**: Pros:
	+ More concise and expressive than `split()`
	+ Can be faster for small to medium-sized strings due to the optimized implementation
Cons:
	+ Less widely supported by older browsers (prior to ES6)
	+ May not work as expected with certain types of separators (e.g., newline characters)

**Other Alternatives**

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

* **`split()` method with separator**: Instead of using an empty string as the separator, try using a non-empty string, such as `str.split('hello')`.
* **Regular expressions**: You could use regular expressions to split the string. For example: `var other = str.match(/./g)`.
* **`Array.prototype.forEach()`**: Instead of using the spread operator or `split()`, you could use a loop to iterate over each character in the string and add it to an array.

Overall, the choice between `split()`, the spread operator, and other alternatives depends on your specific requirements, performance concerns, and personal preference.

str split vs spread (version: 0) Benchmark.js

Comparing performance of: `split vs spread`

Created: 6 years ago by: Guest

Go to the latest result

split

spread

Historical Performance Data aggregated from 23 community runs

Desktop Results:

Chrome 18 runs

Mobile Results:

Chrome 5 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

str split vs spread (version: 0) Benchmark.js

Comparing performance of: split vs spread

Created: 6 years ago by: Guest

Go to the latest result

split

spread

Historical Performance Data aggregated from 23 community runs

Desktop Results:

Chrome 18 runs

Mobile Results:

Chrome 5 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

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Comparing performance of: `split vs spread`