Benchmark: unescape vs replace function

Script Preparation code:

var count = 1000;

Tests:

unescape
for (var i = 0; i < count; i++) { unescape(encodeURI("日")); }
replace func
for (var i = 0; i < count; i++) { encodeURI("日").replace(/%[\da-f]{2}/gi, (char) => String.fromCodePoint(parseInt(char.replace(/%/, ""), 16))); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
unescape
replace func

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):

LLMs can make mistakes. Check important info.

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

**Benchmark Definition**

The benchmark is defined by a JSON object that contains several key pieces of information:

* `Name`: A unique name for the benchmark, which in this case is "unescape vs replace function".
* `Description`: An optional description of the benchmark, which is null in this case.
* `Script Preparation Code` and `Html Preparation Code`: These are scripts or HTML snippets that are used to prepare the environment for the benchmark.

In this case, the script preparation code is a simple variable declaration: `var count = 1000;`. This sets up a variable named `count` with a value of 1000, which will be used in the benchmark. The html preparation code is empty, indicating that no HTML-specific setup is required for this benchmark.

**Individual Test Cases**

The benchmark consists of two individual test cases:

1. **Test Case 1: unescape**
	* `Benchmark Definition`: A JavaScript loop that uses the `unescape` function to decode a Unicode string.
	* `Test Name`: "unescape"

The code is:
```javascript
for (var i = 0; i < count; i++) {
    unescape(encodeURI("日"));
}
```
This test case iterates 1000 times, using the `unescape` function to decode a Unicode string that represents the Japanese character "".

2. **Test Case 2: replace func**
	* `Benchmark Definition`: A JavaScript loop that uses the `replace` function with a regular expression to decode a Unicode string.
	* `Test Name`: "replace func"

The code is:
```javascript
for (var i = 0; i < count; i++) {
    encodeURI("日").replace(/%[\\da-f]{2}/gi, (char) => String.fromCodePoint(parseInt(char.replace(/%/, ""), 16)));
}
```
This test case also iterates 1000 times, but uses the `replace` function with a regular expression to decode the same Unicode string.

**Library**

In this benchmark, there is no explicit library used. However, it's worth noting that JavaScript's built-in functions like `unescape`, `encodeURI`, and `String.fromCodePoint` are part of the standard library.

**Special JS feature or syntax**

There is a special JS feature being used in these test cases: Unicode escape sequences. Specifically, the `\u{...}` notation is used to represent Unicode characters as hexadecimal codes. In this case, the character "" is represented using the `unescape` function, while the same character is decoded using the `replace` function with a regular expression.

**Options compared**

In this benchmark, two different options are being compared:

1. **Using `unescape`**: This option uses the built-in `unescape` function to decode Unicode characters.
2. **Using `replace` with regular expressions**: This option uses the `replace` function with a regular expression to decode Unicode characters.

**Pros and Cons**

Here's a brief summary of the pros and cons of each approach:

1. **Using `unescape`**:
	* Pros: Simple, straightforward implementation.
	* Cons: May not be optimized for performance, as it relies on the browser's built-in decoding logic.
2. **Using `replace` with regular expressions**:
	* Pros: Can provide more control over the decoding process and can be optimized for performance using techniques like caching or memoization.
	* Cons: Requires a good understanding of regular expressions and may be slower than the simple `unescape` implementation.

**Other alternatives**

If you were to reimplement this benchmark with different approaches, some alternative options might include:

1. **Using `Intl` API**: The JavaScript `Intl` API provides support for Unicode normalization and decoding. This could provide a more standardized and efficient way to decode Unicode characters.
2. **Using a third-party library**: Depending on the specific use case, a third-party library like Unicode normalizer or a regex engine might be used to accelerate the decoding process.

Overall, the choice of approach depends on the specific requirements of your project, including performance, code readability, and maintainability considerations.

Latest run results:

Run details: (Test run date: 10 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.36

Browser/OS: Chrome 121 on Windows

View result in a separate tab

Test name	Executions per second
unescape	3135.9 Ops/sec
replace func	1067.7 Ops/sec

Related benchmarks:

unescape vs replace function (version: 0)

Comparing performance of: unescape vs replace func

Created: 10 months ago by: Registered User

Jump to the latest result

unescape

replace func

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):