Benchmark: replaceAll vs regex replace tabs to spaces

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(/\t/g, ' ');
replace All
"this is it".replaceAll("\t", " ");

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

Autogenerated LLM Summary (model llama3.2:3b, generated 25 days ago):

LLMs can make mistakes. Check important info.

Let's break down the provided JSON and explain what's being tested, compared, and what pros and cons are associated with each approach.

**Benchmark Context**

The benchmark is designed to compare two different ways of replacing tabs (`\t`) with spaces in a string. There are two test cases:

1. Using regular expressions (regex) to replace tabs.
2. Defining a custom `replaceAll` function on the `String.prototype`.

**Options Compared**

In this benchmark, we have two options:

a. **Regex Replace**: This approach uses JavaScript's built-in `replace()` method with a regex pattern (`/\\t/g`) to replace all occurrences of `\t` with spaces.

b. **Custom `replaceAll` Function**: This approach defines a custom function on the `String.prototype`, which mimics the behavior of `replace()`. The custom function takes two arguments: `search` and `replacement`.

**Pros and Cons**

Here are some pros and cons associated with each approach:

a. **Regex Replace**

Pros:

* Widely supported by most JavaScript engines.
* Efficient, as it only scans the string once.

Cons:

* May be slower due to the overhead of regex parsing and compilation.
* Can be vulnerable to security issues if not properly sanitized (e.g., using a `RegExp` with user-input data).

b. **Custom `replaceAll` Function**

Pros:

* May be faster, as it avoids the overhead of regex parsing and compilation.
* Allows for more control over the replacement process.

Cons:

* Not widely supported by JavaScript engines, which may affect performance or compatibility.
* Requires careful implementation to ensure correct behavior.

**Library Used (if applicable)**

None. There is no external library used in this benchmark.

**Special JS Features/Syntax**

There are no special JavaScript features or syntax mentioned in the provided code. However, if we were to interpret the `String.prototype.replaceAll` function as using a custom implementation of `replace()`, it might be considered a variant of the standard `replace()` method, which is a part of the ECMAScript specification.

**Alternatives**

If you're interested in exploring alternative approaches, here are some options:

1. **Using a library like `lodash`**: You could use the `_.str.replace()` function from the Lodash library to replace tabs with spaces.
2. **Using `String.prototype.replace()` with a callback**: Instead of defining a custom `replaceAll` function, you could use a callback function as an argument to `replace()`. This approach would be more compatible with older JavaScript engines but might be slower due to the overhead of callback invocation.
3. **Implementing a custom replacement algorithm**: Depending on your specific requirements, you might consider implementing a custom replacement algorithm that's optimized for performance or compatibility.

Keep in mind that these alternatives are not necessarily relevant to this particular benchmark, and their adoption would depend on your specific use case and priorities.

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:95.0) Gecko/20100101 Firefox/95.0

Browser/OS: Firefox 95 on Windows

View result in a separate tab

Test name	Executions per second
replace regex	24595440.0 Ops/sec
replace All	4884761.0 Ops/sec

Related benchmarks:

replaceAll vs regex replace tabs to spaces (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>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 25 days ago):