Benchmark: replace all performance javascript

Script Preparation code:

var reg = / /g;
var str = " ".repeat(10000);

Tests:

replace regex
str.replace(reg, "+");
replace All
str.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: 7 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:143.0) Gecko/20100101 Firefox/143.0

Browser/OS: Firefox 143 on Mac OS X 10.15

View result in a separate tab

Test name	Executions per second
replace regex	6549.2 Ops/sec
replace All	10828.1 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net!

The provided JSON represents two individual test cases, each testing a different approach to replacing all occurrences of whitespace in a string.

**Test Case 1: "replace regex"**

In this test case, the benchmark definition is `str.replace(reg, "+");`. Here, `reg` is a regular expression object (`/ /g`) that matches any whitespace character (`\s`). The replacement value is `"+"`, which means all occurrences of whitespace will be replaced with a single plus sign.

**Pros and Cons:**

Pros:

* This approach is concise and easy to read.
* It uses the built-in `replace()` method, which is a standard JavaScript function.

Cons:

* Replacing whitespace with a single character (`+`) may not be the most efficient or readable solution.
* The replacement value `"+"` may lead to unexpected results if not handled correctly in downstream code.

**Test Case 2: "replace All"**

In this test case, the benchmark definition is `str.replaceAll(" ", "+");`. Here, `replaceAll()` is a method provided by some JavaScript libraries (more on this later), which replaces all occurrences of whitespace characters (`\s`) with a specified value (`"+"`).

Pros:

* This approach uses a well-known and widely-supported method for replacing multiple characters.
* It can be more efficient than the regex approach, especially for large strings.

Cons:

* `replaceAll()` is not a standard JavaScript function (it's a library feature).
* Some older or less compatible browsers may not support this method.

**Library:**

The `replaceAll()` method is often provided by popular JavaScript libraries like jQuery, Lodash, or other utility libraries. This method is designed to replace all occurrences of whitespace characters in a string, making it more readable and efficient than the regex approach.

**Other Considerations:**

When writing benchmarks, it's essential to consider factors like:

* String size: The performance difference between these approaches may be significant for small strings but negligible for large ones.
* Browser support: Some browsers or older versions might not support `replaceAll()` or have different implementation details for the `replace()` method.
* Code readability and maintainability: While conciseness is important, code readability should never come at the cost of performance.

**Alternatives:**

Other approaches to replacing whitespace in a string include:

* Using the `split()`, `join()`, and `trim()` methods:
```javascript
str = str.split(' ').map(x => x + '+').join('');
```
This approach is more verbose but can be more efficient for certain use cases.
* Using a regex with a specific character class (`\s`):
```javascript
str = str.replace(/\s+/g, '+');
```
This approach is similar to the `replaceAll()` method but uses a standard regex instead.

In conclusion, both test cases demonstrate different approaches to replacing whitespace in a string. The choice of approach depends on factors like performance requirements, code readability, and browser support. By considering these factors and exploring alternative solutions, developers can optimize their code for better performance and maintainability.

Related benchmarks:

replace all performance javascript (version: 0)

Comparing performance of: replace regex vs replace All

Created: 5 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):