Benchmark: String split vs Regex 02

Script Preparation code:

var str = 'spotify:artist:3TVXtAsR1Inumwj472S9r4'

Tests:

string.split
str.split(':')[2]
Regex
str.split('spotify:artist:')[1]

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
string.split
Regex

Fastest: N/A

Slowest: N/A

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/79.0.3945.130 Safari/537.36

Browser/OS: Chrome 79 on Windows

View result in a separate tab

Test name	Executions per second
string.split	3979920.8 Ops/sec
Regex	4007782.8 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down what is being tested in this benchmark.

**Benchmark Definition**
The benchmark is defined by the JSON object at the top, which describes the test scenario:
- `Name`: The name of the benchmark, "String split vs Regex 02".
- `Description`: A brief description of the benchmark, which is "String split vs Regex".

**Script Preparation Code and HTML Preparation Code**
The script preparation code contains a JavaScript string variable named `str`, which holds the value `"spotify:artist:3TVXtAsR1Inumwj472S9r4"`.
There is no corresponding HTML preparation code specified.

**Individual Test Cases**
Two individual test cases are defined:
- The first test case uses the `split()` method on the string variable, and its benchmark definition is `"str.split(':')[2]"`. This means that it splits the input string at the colon (`:`) character and then selects the second item from the resulting array (at index 2).
- The second test case uses a regular expression to split the same string, with the benchmark definition being `"str.split('spotify:artist:')[1]"`.

**What is being tested**
The two test cases are comparing the performance of using the `split()` method versus regular expressions for splitting strings in JavaScript. Specifically:
- **`string.split()`**: This method uses a simple array method to split the input string at the specified separator(s). It returns an array of substrings.
- **Regular Expressions (`str.split('spotify:artist:')[1]`)**: This approach uses a regular expression pattern (in this case, `"spotify:artist:"`) to match and split the input string. The `[1]` index is used to access the second item from the resulting array.

**Pros and Cons of Different Approaches**

- **`string.split()`**
  - Pros:
    * Generally faster than regular expressions because it doesn't require parsing the pattern or creating a regex object.
    * Easier to read and understand, especially for simple splits.
  - Cons:
    * Limited flexibility: Can only split on specific separators, which might not match complex text patterns.

- **Regular Expressions (`str.split('spotify:artist:')[1]`)**

- Pros:
    - More flexible than `string.split()`, allowing for more complex pattern matching and splitting.
    - Can handle edge cases, such as splitting at multiple occurrences of the same separator or handling quoted separators.
  - Cons:
    - Generally slower than `string.split()` because it involves creating a regex object, compiling the pattern, and then executing the match function.
    - More difficult to read and understand, especially for complex patterns.

**Other Considerations**

- **Library Usage**: There is no explicit mention of any external libraries being used in this benchmark. However, JavaScript's built-in `split()` method uses a simple parsing algorithm that doesn't rely on any external dependencies.

- **Special JS Features or Syntax**: There are no special features or syntax mentioned in the provided code snippet. If there were any advanced features like async/await or classes, they would be used to make the benchmarking process more complex and require additional consideration for fairness and accuracy.

**Alternatives**

Some alternative approaches for string splitting could include:
- **`String.prototype.replace()` with a callback function**: This method can be used to replace substrings based on a pattern. However, it might not provide the same level of efficiency as `string.split()`.
- **`Array.prototype.map()` or `Array.prototype.filter()`**: These methods can be used to create new arrays from existing data by applying transformations. However, they would require an additional step to extract individual elements from the resulting array.
- **Other libraries or frameworks for string manipulation**, such as moment.js for date and time parsing or numeral.js for formatting numbers.

Related benchmarks:

String split vs Regex 02 (version: 0)

String split vs Regex

Comparing performance of: string.split vs Regex

Created: 6 years ago by: Guest

Jump to the latest result

string.split

Regex

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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