Benchmark: chars get replace

HTML Preparation code:

<div>String</div>

Script Preparation code:

var str = ".class";

Tests:

charAt
var l = str.charAt(0);
[0]
var l = str[0];
replace
var l = str.replace('.', '');
substr
var l = str.substr(1);
substring
var l = str.substring(1);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
charAt
[0]
replace
substr
substring

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks!

**Benchmark Definition**

The benchmark definition is a JSON object that contains metadata about the test case. Here, we have:

* `Name`: The name of the benchmark (in this case, "chars get replace").
* `Description`: An empty string, indicating that no description is provided.
* `Script Preparation Code` and `Html Preparation Code`: These are code snippets used to prepare the input data for the test case. In this case, we have a JavaScript variable `str` initialized with the value ".class". The HTML preparation code creates an HTML element containing the string "String".

**Individual Test Cases**

The benchmark consists of five test cases:

* `charAt`: Tests the `charAt()` method, which returns the character at a specified index.
* `[0]`: Tests array indexing using square brackets (`[]`) to access the first character of the string. This is equivalent to calling the `charAt(0)` method.
* `replace`: Tests the `replace()` method, which replaces substrings with another value.
* `substr` and `substring`: Test methods that extract substrings from a given string.

**Options Compared**

Here are the options being compared:

1. **Character Access**: Three methods are tested: `charAt()`, `[0]`, and both `substr(1)` and `substring(1)`. The choice of method affects how the first character is accessed.
2. **Substring Extraction**: Two methods are tested: `substr()` and `substring()`. These methods differ in their behavior when extracting substrings.

**Pros and Cons**

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

* **Character Access**:
	+ `[0]`: Fast, simple, and widely supported. However, it only accesses the first character.
	+ `charAt(0)`: More readable and explicit, but might incur additional overhead due to method call.
	+ `substr(1)` and `substring(1)`: Faster than accessing individual characters with `[0]`, as they skip over the character being replaced. However, their behavior is less intuitive for readers unfamiliar with these methods.
* **Substring Extraction**:
	+ `substr(1)` and `substring(1)`: More efficient than using a loop to extract substrings. However, their names might be less familiar or more confusing for some readers.

**Special JavaScript Features**

In this benchmark:

* None of the test cases rely on special JavaScript features like ES6 syntax (e.g., arrow functions, destructuring), async/await, or Promises.
* No libraries are used in these individual test cases.

**Alternatives**

Other alternatives for character access and substring extraction include:

* For character access:
	+ Using `str.length` to check the length of the string instead of accessing individual characters.
	+ Using a loop to iterate over each character in the string.
* For substring extraction:
	+ Using regular expressions (regex) to extract substrings, which can be more flexible but also slower.
	+ Creating a new string by concatenating or repeating the desired substring.

Note that these alternatives might not provide significant performance benefits for small strings and may even incur additional overhead due to the complexity of their implementation.

Latest run results:

Run details: (Test run date: 7 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/57.0.2987.133 Safari/537.36

Browser/OS: Chrome 57 on Windows

View result in a separate tab

Test name	Executions per second
charAt	11151449.0 Ops/sec
[0]	11157605.0 Ops/sec
replace	3963099.5 Ops/sec
substr	9318702.0 Ops/sec
substring	9655338.0 Ops/sec

Related benchmarks:

chars get replace (version: 0)

Comparing performance of: charAt vs [0] vs replace vs substr vs substring

Created: 7 years ago by: Registered User

Jump to the latest result

charAt

[0]

replace

substr

substring

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):