Benchmark: String.proptotype.split vs spread operator

Tests:

split from String
const someString = 'some string detected'; const splittedStr = someString.split('');
split with spread operator
const someString = 'some string detected'; const splittedStr = [...someString];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
split from String
split with spread operator

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 dive into the world of JavaScript microbenchmarks.

**What is being tested?**

The provided benchmark tests the performance difference between two approaches for splitting a string in JavaScript:

1. `String.prototype.split('')`: This method splits a string into an array of substrings using a regular expression with an empty string as the separator.
2. Spread operator (`[...]`): This syntax creates a new array from the elements of a string.

**Options compared**

The benchmark compares these two approaches, which can be considered as different optimization strategies:

* **String splitting**: The first approach uses `String.prototype.split('')`, while the second approach uses the spread operator. Both methods have their own strengths and weaknesses.
* **Regular expressions vs. simple iteration**: The first approach uses a regular expression with an empty string as the separator, which is not very efficient. In contrast, the spread operator simply iterates over each character in the string to create the array.

**Pros and cons of each approach**

1. **String.prototype.split('')**:
	* Pros: Simple and widely supported.
	* Cons:
		+ Not very efficient due to the use of regular expressions.
		+ Can be slower than the spread operator for large strings.
2. **Spread operator (`[...]`)**:
	* Pros:
		+ More efficient, especially for large strings.
		+ Simple and easy to implement.
	* Cons:
		+ May not work as expected in all situations (e.g., Unicode characters).
		+ Less widely supported than `String.prototype.split('')`.

**Library and purpose**

There is no specific library used in this benchmark. However, the spread operator relies on the **Array constructor**, which creates a new array from an iterable.

**Special JS feature or syntax**

The use of the spread operator (`[...]`) introduces a special JavaScript feature called **Destructuring assignment**. This syntax allows for creating a new array by iterating over each element of a string, assigning it to individual elements in the resulting array.

Other alternatives

Some alternative approaches for string splitting could be:

* Using `String.prototype.split()` with a non-empty separator (e.g., `" "`).
* Using `String.fromCharCode()` and indexing into the resulting code unit values.
* Using a library like **Lodash** or **Underscore.js**, which provide more efficient string manipulation methods.

Keep in mind that these alternatives may not be as simple to implement or may have different performance characteristics compared to the spread operator.

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/85.0.4183.121 Safari/537.36

Browser/OS: Chrome 85 on Windows

View result in a separate tab

Test name	Executions per second
split from String	7019413.5 Ops/sec
split with spread operator	6322153.5 Ops/sec

Related benchmarks:

String.proptotype.split vs spread operator (version: 0)

Comparing performance of: split from String vs split with spread operator

Created: 5 years ago by: Guest

Jump to the latest result

split from String

split with spread operator

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):