Benchmark: String.prototype.split vs String.prototype.match

Script Preparation code:

var string = 'Of course I do. Just a second, let\'s see if I could find it.';

Tests:

String.prototype.split
string.split(' ').length - 1;
String.prototype.match
string.match(/ /g).length;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
String.prototype.split
String.prototype.match

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what's being tested, compared options, pros and cons, and other considerations.

**Benchmark Overview**

The benchmark compares the performance of two JavaScript methods: `String.prototype.split` and `String.prototype.match`, specifically when used to count whitespace characters in a string.

**Test Case 1: String.prototype.split**

* **Benchmark Definition**: `string.split(' ').length - 1;`
* This test case measures how long it takes for the browser to split the input string into an array of substrings using the `split` method with a space character as the separator. The resulting length minus one gives us the total number of whitespace characters in the original string.
* **Pros**:
	+ Simple and straightforward implementation
	+ Easy to understand and optimize
* **Cons**:
	+ May not work well for strings containing non-space whitespace characters (e.g., tabs, newline)
	+ Can be slower than `String.prototype.match` due to the overhead of creating an array

**Test Case 2: String.prototype.match**

* **Benchmark Definition**: `string.match(/ /g).length;`
* This test case measures how long it takes for the browser to find and count all occurrences of whitespace characters in the input string using the `match` method with a regular expression.
* **Pros**:
	+ Can handle non-space whitespace characters (e.g., tabs, newline)
	+ Often faster than `String.prototype.split` due to the efficiency of regular expressions
* **Cons**:
	+ May be slower for strings without whitespace characters
	+ Requires a regular expression engine, which can introduce additional overhead

**Library Usage**

In this benchmark, the `String.prototype` methods are used without any external libraries. These methods are part of the standard JavaScript object and are implemented by each browser vendor.

However, it's worth noting that some browsers may use internal optimizations or heuristics when implementing these methods, which could affect the benchmark results.

**Special JS Feature/Syntax**

None mentioned in this specific benchmark. However, it's worth mentioning that regular expressions like `/ /g` can be used to match whitespace characters and flags like `g` (global) are often used to find all matches in a string.

**Alternative Approaches**

Other ways to count whitespace characters include:

* Using the `charCodeAt()` method to iterate over each character in the string and increment a counter for whitespace characters.
* Using the `Array.prototype.filter()` method to create an array of whitespace characters and then use the `length` property to get the count.

These alternative approaches may be slower or more memory-intensive than using the `String.prototype.split` and `String.prototype.match` methods, but they can provide insight into the performance characteristics of these methods.

**Considerations**

* Browser vendor-specific optimizations: Different browsers may optimize the `String.prototype.split` and `String.prototype.match` methods differently, which could affect benchmark results.
* Input string size and complexity: The length and complexity of the input string can significantly impact performance. Larger or more complex strings may require more CPU cycles to process.
* Regular expression engine optimization: Modern browsers have optimized regular expression engines that can provide faster performance for certain types of regular expressions.

I hope this explanation helps!

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/111.0.0.0 Safari/537.36

Browser/OS: Chrome 111 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
String.prototype.split	6654235.5 Ops/sec
String.prototype.match	3469797.0 Ops/sec

Related benchmarks:

String.prototype.split vs String.prototype.match (version: 0)

Use String.prototype.split with a string and String.prototype.match with a regexp to test how many whitespaces are in a string.

Comparing performance of: String.prototype.split vs String.prototype.match

Created: 3 years ago by: Guest

Jump to the latest result

String.prototype.split

String.prototype.match

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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