Benchmark: replace + regex vs replaceAll + string

Tests:

replaceAll + string
'test this string'.replaceAll(' ', '')
replace + regex
'test this string'.replace(/\s+/g, '')

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
replaceAll + string
replace + regex

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 29 days ago):

LLMs can make mistakes. Check important info.

I'd be happy to explain what's being tested in this benchmark.

**What is being tested?**

The provided JSON represents two individual test cases for a JavaScript microbenchmark. The goal of these tests is to compare the performance of two approaches for replacing whitespace characters (`\s`) with an empty string:

1. `replaceAll + string`: This approach uses the built-in `replaceAll()` method, which is a part of the String object in JavaScript.
2. `replace + regex`: This approach uses a regular expression (regex) with the `replace()` method.

**Options compared**

The two approaches are being compared in terms of their execution speed and efficiency.

**Pros and cons of each approach:**

1. **replaceAll + string**:
	* Pros:
		+ Simple to use and understand.
		+ No need to create or compile a regex pattern.
	* Cons:
		+ May be slower than the regex approach, especially for large strings, due to the overhead of searching and replacing substrings.
2. **replace + regex**:
	* Pros:
		+ Can be faster than `replaceAll + string` because it can take advantage of optimizations in the regex engine.
		+ Allows for more flexibility and customization with regular expressions.
	* Cons:
		+ Requires a basic understanding of regex patterns, which can be complex.
		+ May require more resources (e.g., memory) to execute.

**Library and purpose**

There is no explicit library mentioned in the provided JSON. However, it's likely that the `replaceAll()` method uses an implementation that relies on native JavaScript functionality, whereas the `replace()` method with a regex pattern may use an external library or engine (e.g., V8 for Chrome) to execute the regular expression.

**Special JS feature or syntax**

There is no special JavaScript feature or syntax mentioned in the provided JSON. The tests only involve standard JavaScript methods and operators.

**Other alternatives**

Other alternatives for replacing whitespace characters with an empty string might include:

1. Using a library like `lodash` that provides utility functions for working with strings.
2. Implementing a custom function using bitwise operations to remove whitespace characters.
3. Using a different approach, such as using the `trim()` method followed by concatenation or string manipulation.

However, these alternatives are not being tested in this specific benchmark.

**Benchmark preparation code and test cases**

The provided JSON includes:

1. A single benchmark definition that defines two test cases:
	* `replaceAll + string`: Uses a hardcoded regex pattern to replace whitespace characters with an empty string.
	* `replace + regex`: Uses a similar hardcoded regex pattern as the previous test, but with a call to the `replace()` method instead of `replaceAll()`.
2. Individual test case definitions that provide a specific input string (`'test this string'`) and a unique name for each test.

The benchmark result includes performance metrics (e.g., executions per second) for each test case on a specific browser and device platform.

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36

Browser/OS: Chrome 97 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
replaceAll + string	9238001.0 Ops/sec
replace + regex	11838585.0 Ops/sec

Related benchmarks:

replace + regex vs replaceAll + string (version: 0)

replace + regex vs replaceAll + string

Comparing performance of: replaceAll + string vs replace + regex

Created: 2 years ago by: Guest

Jump to the latest result

replaceAll + string

replace + regex

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 29 days ago):