Benchmark: for loop vs while splice (destructuring)

Script Preparation code:

sA = new Array(10000);
sA.fill('-');

Tests:

for
for (let i = 0; i < sA.length; i++) { const a = sA[i]; const b = sA[i]; const c = sA[i]; }
while destruct
while (sA.length) { const [a, b, c] = sA.splice(0, 3); }
while classic
while (sA.length) { const newA = sA.splice(0, 3); const a = newA[i]; const b = newA[i]; const c = newA[i]; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for
while destruct
while classic

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's break down the provided JSON and explain what is being tested, the options being compared, and their pros and cons.

**Benchmark Definition**

The benchmark definition represents a JavaScript microbenchmark that compares three approaches for extracting values from an array:

1. **For Loop**: A traditional for loop that iterates over the array and extracts values.
2. **While Splice (Destructuring)**: A while loop that uses the `splice` method to remove elements from the array and destructures the extracted value into three variables using array destructuring syntax (`const [a, b, c] = ...`).
3. **While Classic**: A similar while loop to the second option, but without destructuring syntax.

**Options Being Compared**

The two main options being compared are:

* **For Loop vs While Splice (Destructuring)**: This comparison tests how efficient JavaScript is at extracting values from an array using a for loop versus using a while loop with `splice` and destructuring.
* Within the "While" category, there's another option:
  * **While Classic**: This comparison tests the performance of using `splice` without destructuring syntax in a while loop.

**Pros and Cons**

1. **For Loop**:
   - Pros: Generally more intuitive and easier to understand for some developers.
   - Cons: May be slower due to array indexing and iteration, especially when dealing with large arrays.
2. **While Splice (Destructuring)**:
   - Pros: Can be faster since it avoids unnecessary array indexing by removing elements directly from the original array, reducing overhead.
   - Cons: Requires understanding of `splice` and destructuring syntax, which can be challenging for some developers.
3. **While Classic**:
   - This option is essentially similar to the "For Loop" in terms of performance but lacks the benefit of destructuring syntax.

**Library and Special JS Features**

There's no specific library being used in this benchmark, apart from standard JavaScript features like `splice` and array destructuring. No special JavaScript features or syntax are mentioned.

**Considerations**

- The use of a large array (10,000 elements) to simulate real-world scenarios where performance matters.
- The importance of understanding the intricacies of `splice` for efficient array manipulation.
- Balance between readability and performance considerations in code.

**Alternatives**

If you're looking at alternatives or variations on this benchmark, some possible modifications could include:

* Using a different data structure (e.g., object or set) to test extraction methods.
* Incorporating additional loop optimizations or parallel execution for more complex scenarios.
* Testing the impact of JavaScript engine optimizations (e.g., Safari's Just-In-Time compilation).
* Exploring performance differences with ES6+ features that could affect this benchmark, such as `for...of` loops.

Keep in mind these alternatives would significantly alter the nature of the test, aiming to either simulate different scenarios or evaluate the robustness and adaptability of JavaScript execution engines under various conditions.

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/15.6.1 Safari/605.1.15

Browser/OS: Safari 15 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
for	109.8 Ops/sec
while destruct	3978523.5 Ops/sec
while classic	3967704.0 Ops/sec

Related benchmarks:

for loop vs while splice (destructuring) (version: 0)

for loop vs while splice

Comparing performance of: for vs while destruct vs while classic

Created: 2 years ago by: Guest

Jump to the latest result

for

while destruct

while classic

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):