Benchmark: substring/substr/slice

Script Preparation code:

var timestamp = '2017-09-30T03:57:26.875Z'

Tests:

slice
var result = `[${timestamp.slice(0, 9)} ${timestamp.slice(11, 18)}]`
substring
var result = `[${timestamp.substring(0, 9)} ${timestamp.substring(11, 18)}]`
substr
var result = `[${timestamp.substr(0, 10)} ${timestamp.substr(11, 8)}]`

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
slice
substring
substr

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

I'd be happy to explain what's being tested in this benchmark.

The benchmark is testing the performance of three JavaScript methods: `slice()`, `substring()`, and `substr()` on a specific string. The tests are comparing the execution speed of these methods for extracting two substrings from a timestamp string.

Let's break down each method:

1. `slice()`: Returns a shallow copy of a portion of an array (or string). In this case, it extracts two substrings from the timestamp string.
2. `substring()`: Returns a new string that contains a subset of characters from another string. It also extracts two substrings from the timestamp string.
3. `substr()`: Similar to `substring()`, but without returning a new string; instead, it modifies the original string.

Now, let's discuss the pros and cons of each approach:

* **`slice()`**: Pros:
	+ Creates a shallow copy of the substring, which can be beneficial for avoiding side effects.
	+ Can be more readable when working with arrays or strings.
* Cons:
	+ Creates an intermediate array or string object, which might incur overhead due to memory allocation and copying.
* **`substring()`**: Pros:
	+ Returns a new string, avoiding potential side effects on the original string.
	+ Can be more efficient than `slice()`, as it doesn't create an intermediate array or string object.
* Cons:
	+ Might not be suitable for large strings, as creating a new string object can consume memory.
* **`substr()`**: Pros:
	+ Similar to `substring()`, but without the overhead of creating a new string object.
	+ Can be beneficial when working with large strings, as it avoids the creation of an intermediate string object.

Other considerations:

* The benchmark is using the latest JavaScript engine (Firefox 97) and platform (Windows Desktop).
* The tests are executed in succession, which means that the results might not accurately reflect the performance of each method if they were executed concurrently.
* There's no consideration for browser-specific optimizations or features.

As for libraries used in the test cases, none are mentioned. The code relies solely on built-in JavaScript methods and variables.

There are alternative approaches to testing the performance of these methods, such as:

1. Using a virtual DOM library like React or Vue.js to simulate real-world scenarios.
2. Utilizing a string manipulation library like String.prototype.replace() or Intl.Collator API for Unicode-aware comparisons.
3. Employing profiling tools or benchmarking libraries specifically designed for JavaScript, like Benchmark.js or js-benchmark.

Keep in mind that these alternatives might add complexity and require more setup than the simple test cases presented here.

If you have any further questions or would like to discuss this topic in more detail, feel free to ask!

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:97.0) Gecko/20100101 Firefox/97.0

Browser/OS: Firefox 97 on Windows

View result in a separate tab

Test name	Executions per second
slice	27112412.0 Ops/sec
substring	27753238.0 Ops/sec
substr	25193894.0 Ops/sec

Related benchmarks:

substring/substr/slice (version: 0)

Comparing performance of: slice vs substring vs substr

Created: 3 years ago by: Guest

Jump to the latest result

slice

substring

substr

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):