Benchmark: replaceAll vs regex replace compiled

Tests:

replace regex
"this is it".replace(new RegExp(" ", '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: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36

Browser/OS: Chrome 122 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
replace regex	3054130.2 Ops/sec
replace All	6783940.5 Ops/sec

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

LLMs can make mistakes. Check important info.

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

The provided JSON represents a JavaScript microbenchmark that compares two approaches for replacing whitespace characters with a plus sign in a string:

1. Using `String.prototype.replace()` method with a regular expression (regex) pattern (`" \", 'g'`) to replace all occurrences of one or more whitespace characters.
2. Using the `replaceAll()` method, which is not a standard JavaScript method. Instead, it's likely a custom implementation.

Now, let's discuss the pros and cons of each approach:

**Using `String.prototype.replace()` with regex:**

Pros:

* This method is widely supported by most modern browsers and Node.js versions.
* It allows for more complex pattern matching, such as escaping special characters.
* The performance should be similar across different browsers.

Cons:

* Requires defining a regular expression pattern, which can be error-prone if not done correctly.
* May incur overhead due to the need to parse the regex pattern.

**Using `replaceAll()` (custom implementation):**

Pros:

* May provide better performance due to optimized code and potentially reduced overhead.
* Eliminates the need to define a regex pattern, making it easier to use.

Cons:

* This method is not widely supported by browsers or Node.js versions. It may only work in specific environments or with custom implementations.
* Performance results might vary across different browsers and platforms.

Other considerations:

* Both approaches replace all whitespace characters (`\s`) with a plus sign (`+`).
* The test case uses `const` for string literals, which is a modern JavaScript feature (introduced in ES6).

Now, let's take a look at the library used in this benchmark: **none**.

There are no external libraries mentioned in the provided JSON.

Regarding special JS features or syntax:

* As mentioned earlier, the test case uses `const` for string literals, which is a modern JavaScript feature (introduced in ES6).

If you're interested in exploring other alternatives or optimizations, here are some options to consider:

1. **Use a more efficient regex pattern**: For example, using `\s+` instead of `" \", 'g'`.
2. **Leverage browser-specific optimizations**: Some browsers may optimize string replacements using `replaceAll()` or similar methods.
3. **Experiment with different implementation details**: Adjusting the implementation of `replaceAll()` or other custom methods to optimize performance.

Keep in mind that these alternatives might not be supported by all browsers or environments, so it's essential to test and verify their results before making any optimizations.

Related benchmarks:

replaceAll vs regex replace compiled (version: 0)

Comparing performance of: replace regex vs replace All

Created: 2 years ago by: Guest

Jump 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):