Benchmark: dropWhile comparison

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var first = [...Array(100)].map(it => ~~(Math.random() * 1000));
var second = [...Array(20)].map(it => ~~(Math.random() * 1000));

Tests:

Function 1
function dropWhile(arr, pred) { for (var i = 0; i < arr.length && pred(arr[i]); ++i) ; return arr.slice(i) } dropWhile(first, x => !second.includes(x))
Function 2
function dropWhile(array, cb) { const n = array.length; let i = 0; for (; i < n; i++) { if (!cb(array[i])) { break; } } return array.slice(i); } dropWhile(first, x => !second.includes(x))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Function 1
Function 2

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gemma2:9b, generated 27 days ago):

LLMs can make mistakes. Check important info.

This benchmark tests different implementations of the `dropWhile` function in JavaScript.  The `dropWhile` function takes an array and a predicate function as arguments. It returns a new array containing all elements from the original array that are *after* the first element which does not satisfy the predicate function.

**Let's break down the test cases:**

* **Function 1:** This implementation uses a `for` loop to iterate through the array and checks if the current element satisfies the predicate. It continues iterating until it finds an element that doesn't satisfy the predicate, then returns a slice of the array starting from that index.
   * **Pros:** Potentially simpler to understand for beginners.
   * **Cons:** Might be less efficient than other approaches due to potentially iterating through unnecessary elements.

* **Function 2:** This implementation is similar to Function 1 but uses a `while` loop and breaks out of the loop when an element doesn't satisfy the predicate.
   * **Pros:** Can be slightly more concise than using a `for` loop in some cases.
   * **Cons:**  Similar efficiency concerns as Function 1.

**Alternatives:**

* **Using `filter()`:** A more functional approach is to use the built-in `filter()` method to filter the array after dropping elements based on the predicate. This often leads to more readable and efficient code.
    ```javascript
    first.filter(x => !second.includes(x))
    ```

* **Using Lodash's `dropWhile`:**  The benchmark includes a reference to the Lodash library, which provides a built-in `dropWhile()` function that might be more efficient and optimized for performance.

**Important Considerations:**

* **Data Size:** The size of the input array significantly impacts performance. These benchmarks are likely testing small arrays, so results may not scale linearly to larger datasets.
* **Predicate Complexity:** The complexity of the predicate function also plays a role in performance. A complex predicate might require more computation time for each element, affecting overall execution speed.
* **Profiling Tools:** For more detailed insights into performance bottlenecks, consider using JavaScript profiling tools like Chrome DevTools Profiler to analyze execution times and identify areas for optimization.

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/106.0.0.0 Safari/537.36

Browser/OS: Chrome 106 on Linux

View result in a separate tab

Test name	Executions per second
Function 1	603339.6 Ops/sec
Function 2	597686.5 Ops/sec

Related benchmarks:

dropWhile comparison (version: 2)

Comparing performance of: Function 1 vs Function 2

Created: one year ago by: Registered User

Jump to the latest result

Function 1

Function 2

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gemma2:9b, generated 27 days ago):