Benchmark: Test AAAAA - MeasureThat.net

Tests:

A
const ALLOW_LETTERS = 2; const REPLACER = '*'; var value = "ok123"; var result = value.slice(0, ALLOW_LETTERS) + REPLACER.repeat(value.length - ALLOW_LETTERS);
B
const ALLOW_LETTERS = 2; const REPLACER = '*'; var value = "ok123"; var result = value.split('').map(function(letter, index) { if (index >= ALLOW_LETTERS && !/\s/.test(letter)) { return REPLACER; } return letter; }).join('');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
A
B

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Measuring JavaScript performance is an essential task for developers, and MeasureThat.net provides a convenient platform for benchmarking.

The provided JSON data represents two test cases (A and B) for measuring the performance of JavaScript string manipulation operations.

**Benchmark Definition:**
The benchmark definition specifies the code to be executed during the benchmark. In this case, both tests involve manipulating strings using a fixed-length replacement pattern. The main difference between the two tests lies in the approach used:

**Test A:** Uses `slice()` and `repeat()`
```javascript
var result = value.slice(0, ALLOW_LETTERS) + REPLACER.repeat(value.length - ALLOW_LETTERS);
```

* **Pros:**
	+ Simple and straightforward implementation.
	+ Easy to understand and maintain.
* **Cons:**
	+ May not be optimized for performance, as it uses multiple function calls.

**Test B:** Uses `split()`, `map()`, and `join()`
```javascript
var result = value.split('').map(function(letter, index) {
    if (index >= ALLOW_LETTERS && !/\\s/.test(letter)) {
        return REPLACER;
    }
    return letter;
}).join('');
```

* **Pros:**
	+ Can be optimized for performance using array methods.
	+ More expressive and flexible code structure.
* **Cons:**
	+ May have a steeper learning curve due to the use of advanced JavaScript features.

**Other considerations:**

* **String manipulation patterns:** Both tests involve replacing characters in a string based on their position. This pattern is common in various string processing tasks, making it a good choice for benchmarking.
* **Browser-specific optimizations:** Modern browsers often provide optimized string manipulation functions (e.g., `String.prototype.replace()`) that can outperform simple implementations like those shown above.

**Library usage:**
None of the provided test cases use any external libraries. However, MeasureThat.net itself relies on various libraries and frameworks for its functionality.

**Special JS features:**
Neither test case uses special JavaScript features like ES6 modules, async/await, or `const` expressions with let declarations.

Now that you know what's being benchmarked, here are some alternative approaches to consider:

1. **Other string manipulation functions:** Explore other built-in string methods, such as `String.prototype.replace()`, `String.prototype.substring()`, or `Array.prototype.slice()`.
2. **Third-party libraries:** Research and use popular JavaScript libraries like Lodash, Underscore.js, or String-promise (a promise-based library for string manipulation).
3. **Custom implementation optimizations:** Experiment with custom optimization techniques, such as caching, memoization, or parallel processing.
4. **Performance testing frameworks:** Use dedicated performance testing frameworks like Benchmark.js, WebPageTest, or Google's Chrome DevTools Performance profiling.

Latest run results:

Run details: (Test run date: 8 days ago)

User agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:131.0) Gecko/20100101 Firefox/131.0

Browser/OS: Firefox 131 on Ubuntu

View result in a separate tab

Test name	Executions per second
A	27319400.0 Ops/sec
B	3235767.0 Ops/sec

Related benchmarks:

Test AAAAA (version: 0)

Comparing performance of: A vs B

Created: 8 days ago by: Guest

Jump to the latest result

A

B

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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