Benchmark: replaceAll vs regex replace made in beethovben

Script Preparation code:

String.prototype.replaceAll = function(search, replacement) {
    var target = this;
    return target.replace(new RegExp(search, 'g'), replacement);
};

Tests:

replace regex
"this is it".replace(/ /g, "+");
replace All
"this is it".replaceAll(/ /, "+");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
replace regex
replace All

Fastest: N/A

Slowest: N/A

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/132.0.0.0 Safari/537.36

Browser/OS: Chrome 132 on Mac OS X 10.15.7

View result in a separate tab

replace regex

10.8M/s

replace All

5.6M/s

View exact numbers

Test name	Executions per second
✓ replace regex	10,798,766 Ops/sec
replace All	5,564,482 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Overview**
The benchmark compares two approaches to replace substrings in a string: using the `String.prototype.replace()` method with a regular expression (regex) and using a custom function called `replaceAll()`. The test aims to determine which approach is faster and more efficient.

**Options compared**

1. **`replace()` with regex**: This option uses the built-in `replace()` method of the String prototype, but provides a custom search pattern using a regex. The regex is executed with the `g` flag (global) at the end, meaning it will replace all occurrences of the pattern in the string.
2. **`replaceAll()`**: This is the custom function defined in the benchmark's Script Preparation Code. It takes two arguments: the search pattern and the replacement string.

**Pros and cons**

1. `replace()` with regex:
	* Pros:
		+ Widely supported and well-optimized by browsers.
		+ Can handle more complex patterns, such as anagrams or Unicode characters.
	* Cons:
		+ May be slower due to overhead from the regex engine.
		+ Less control over the replacement process (e.g., no ability to specify a replacement string).
2. `replaceAll()`: This custom function provides more control over the replacement process but may have a performance penalty due to its custom implementation.

**Library used**
None is explicitly mentioned, as this benchmark focuses on the JavaScript engine's behavior rather than any external libraries.

**Special JS feature or syntax**
The test uses a feature called "arrow functions" (e.g., `String.prototype.replaceAll = function(search, replacement) { ... }`). This is not specific to the benchmark itself but is a common pattern in modern JavaScript. The test also uses template literals (`"\"this is it\".replace(/ /g, \"+\");"`), which are available in ECMAScript 2015 (ES6) and later versions.

**Other alternatives**

If you were to rewrite this benchmark using different approaches or libraries, some options could include:

1. Using a library like `regex-escape` to generate escaped patterns for the regex.
2. Implementing a custom replacement function using `Set` data structures.
3. Comparing the performance of using strings as regular expressions versus using `RegExp` constructors.

Keep in mind that these alternatives would change the fundamental nature of the benchmark, and you'd need to adjust the test cases and expected results accordingly.

replaceAll vs regex replace made in beethovben (version: 0)

Comparing performance of: `replace regex vs replace All`

Created: 5 years ago by: Guest

Go to the latest result

replace regex

replace All

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

replaceAll vs regex replace made in beethovben (version: 0)

Comparing performance of: replace regex vs replace All

Created: 5 years ago by: Guest

Go to the latest result

replace regex

replace All

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: `replace regex vs replace All`