Benchmark: Replace vs Slice

Script Preparation code:

var command = '/ping'
var prefix = '/'

Tests:

Replace
command.replace(prefix, '')
Slice
command.slice(prefix.length).trim()

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Replace
Slice

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/107.0.0.0 Safari/537.36

Browser/OS: Chrome 107 on Windows

View result in a separate tab

Test name	Executions per second
Replace	3489015.8 Ops/sec
Slice	4948072.5 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what's being tested, compared, and their pros and cons.

**Benchmark Definition**

The benchmark definition is a JSON object that describes the test case. In this case:

* "Name" is a human-readable name for the benchmark.
* "Description" provides a brief explanation of what the test case does.
* "Script Preparation Code" defines the JavaScript code executed before running the test case. In this case, it sets two variables: `command` and `prefix`, where `command` is set to a string containing "/ping" followed by a newline character (`\r\n`), and `prefix` is set to a forward slash (`/`).
* "Html Preparation Code" is empty in this case.

**Individual Test Cases**

There are two test cases:

1. **Replace**
	* The benchmark definition is `command.replace(prefix, '')`.
	* This test case replaces the first character of the `command` string with an empty string, effectively removing the prefix.
2. **Slice**
	* The benchmark definition is `command.slice(prefix.length).trim()`.
	* This test case uses the `slice()` method to extract a subset of characters from the `command` string, starting from the length of the `prefix`, and then removes leading and trailing whitespace using the `trim()` method.

**Comparison**

The two test cases are comparing the performance of these two approaches:

1. **String Replacement (`replace()`)**
	* Pros:
		+ Can be more efficient when only replacing a single character.
		+ May be faster for small prefixes.
	* Cons:
		+ Creates a new string object, which can lead to memory allocation overhead.
		+ May not be suitable for large prefixes or strings with complex patterns.
2. **String Slicing (`slice()`)**
	* Pros:
		+ Can be more efficient when working with large strings or prefixes.
		+ Avoids creating a new string object, reducing memory allocation overhead.
	* Cons:
		+ May require additional character indexing or arithmetic operations.
		+ Can lead to slightly slower performance for small prefixes.

**Other Considerations**

When choosing between `replace()` and `slice()`, consider the following factors:

* **Prefix length**: For short prefixes, `replace()` might be faster due to its simplicity. However, as prefix lengths increase, `slice()` becomes more efficient.
* **String complexity**: If the string contains complex patterns or characters, `replace()` may be slower due to regular expression overhead. In such cases, `slice()` can provide better performance.
* **Performance critical code**: If you're working on performance-critical code and need to remove prefixes from strings frequently, consider using `slice()` for its potential efficiency gains.

**Library Usage**

There's no explicit library usage in this benchmark definition. However, if you're interested in exploring other approaches or testing different libraries, some alternatives include:

* **Regexp**: Using regular expressions can provide more flexibility and accuracy when removing prefixes. However, it may also come with performance overhead.
* **String manipulation libraries**: Libraries like `lodash` offer optimized string manipulation functions that might be faster than the built-in methods.

**Special JS Features or Syntax**

There are no special JavaScript features or syntax used in this benchmark definition.

Related benchmarks:

Replace vs Slice (version: 0)

Strip off the prefix from string

Comparing performance of: Replace vs Slice

Created: 2 years ago by: Guest

Jump to the latest result

Replace

Slice

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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