Benchmark: Counting words space - match vs split

Script Preparation code:

var regex = /\s/
var regexGlobal = /\s/g
var str = 'foo bar baz\n\nfoo bar'

Tests:

Split
str.split(regex).length
Match
str.match(regexGlobal).length

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Split
Match

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 6 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36

Browser/OS: Chrome 65 on Mac OS X 10.13.3

View result in a separate tab

Test name	Executions per second
Split	1456970.8 Ops/sec
Match	1537889.9 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what's being tested.

**Benchmark Description**

The benchmark is designed to compare two approaches for counting words in a string: `str.split(regex)` and `str.match(regexGlobal)`. The goal is to determine which approach is faster, more efficient, or both.

**Options Compared**

Two options are compared:

1. **`str.split(regex)`**: This method splits the input string `str` into an array of words using a regular expression `regex`. The `\s` pattern matches any whitespace character (including spaces, tabs, and newline characters). By default, the `g` flag at the end of the regex makes it match all occurrences in the string.
2. **`str.match(regexGlobal)`**: This method returns an array containing one or more matches of the regular expression `regexGlobal` within the input string `str`. The `\s` pattern is used as before, and the `g` flag ensures that all matches are found.

**Pros and Cons**

**Split ( regex )**

Pros:

* Can be more efficient for larger strings since it avoids creating an array of words.
* Some browsers may cache the split result, making subsequent calls faster.

Cons:

* May not handle edge cases like newline characters correctly if not properly escaped in the regex.
* Requires proper escape handling to avoid unexpected behavior.

**Match ( regexGlobal )**

Pros:

* Handles whitespace characters correctly without requiring escape handling.
* May be more suitable for strings with varying whitespace formats.

Cons:

* Can be slower than split, especially for large strings due to the overhead of creating an array and calling a function.
* Some browsers may not cache match results, leading to slower performance on subsequent calls.

**Library and Purpose**

The `match` method uses the `String.prototype.match()` method, which is a built-in JavaScript method that returns an array containing one or more matches of the regular expression within the string. The `regexGlobal` variable contains the modified regex pattern with the `\s` character included for whitespace matching.

**Special JS Features**

The benchmark uses regular expressions (regex) to match and split strings. Regular expressions are a powerful feature in JavaScript that allows you to search, validate, and extract patterns from text.

**Other Considerations**

* The benchmark measures the execution time of each method, so it's essential to ensure that both methods produce identical results for accurate comparisons.
* If possible, consider using a more modern approach, like using `str.split()` with the `g` flag or `String.prototype.matchAll()`, which can provide better performance and handling of edge cases.

**Alternatives**

Other approaches you could consider include:

1. **Using a library**: Depending on your specific requirements, you might want to use a library like `lodash` that provides optimized string manipulation methods.
2. **Native methods**: Consider using native JavaScript methods like `String.prototype.replaceAll()` or `Array.prototype.map()` for more efficient processing of strings.
3. **Browser-specific optimizations**: Some browsers have built-in optimizations for specific string operations, so it's worth checking the documentation for your target browsers to see if they provide any advantages.

Keep in mind that this is just a starting point, and you may need to experiment with different approaches to find the most suitable solution for your particular use case.

Related benchmarks:

Counting words space - match vs split (version: 2)

Comparing performance of: Split vs Match

Created: 6 years ago by: Registered User

Jump to the latest result

Split

Match

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):