Benchmark: Array item swapping, destructuring vs temp variable (throwaway destructuring)

Array item swapping, destructuring vs temp variable (throwaway destructuring) (version: 1)

Array destructuring vs temp variable use in array item swapping

Comparing performance of: Length 10 temp swap vs Length 10 destructuring swap vs Length 100 temp swap vs Length 100 destructuring swap vs Length 1000 temp swap vs Length 1000 destructuring swap

Created: 12 days ago by: Guest

Jump to the latest result

Script Preparation code:

function tempSwap(array) {
    const length = array.length;
    const swap1 = Math.floor(Math.random() * length);
    const swap2 = Math.floor(Math.random() * length);
    const temp = array[swap1];

    array[swap1] = array[swap2];
    array[swap2] = array[temp];
}

function destructuringSwap(array) {
    const length = array.length;
    const swap1 = Math.floor(Math.random() * length);
    const swap2 = Math.floor(Math.random() * length);

    [
        array[swap1],
        array[swap2]
    ] = [
        array[swap2],
        array[swap1]
    ];
}

Tests:

Length 10 temp swap
tempSwap(new Array(10));
Length 10 destructuring swap
destructuringSwap(new Array(10));
Length 100 temp swap
tempSwap(new Array(100));
Length 100 destructuring swap
destructuringSwap(new Array(100));
Length 1000 temp swap
tempSwap(new Array(1000));
Length 1000 destructuring swap
destructuringSwap(new Array(1000));

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Length 10 temp swap
Length 10 destructuring swap
Length 100 temp swap
Length 100 destructuring swap
Length 1000 temp swap
Length 1000 destructuring swap

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 12 days ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36 Edg/135.0.0.0

Browser/OS: Chrome 135 on Windows

View result in a separate tab

Test name	Executions per second
Length 10 temp swap	17986974.0 Ops/sec
Length 10 destructuring swap	24715506.0 Ops/sec
Length 100 temp swap	10699824.0 Ops/sec
Length 100 destructuring swap	13495602.0 Ops/sec
Length 1000 temp swap	2290509.5 Ops/sec
Length 1000 destructuring swap	2260521.2 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated 12 days ago):

LLMs can make mistakes. Check important info.

This benchmark compares two different methods for swapping items in an array: using a temporary variable and using array destructuring. The primary focus is on their performance at different array sizes: 10, 100, and 1000 elements.

### Methods Compared

1. **Temporary Variable Swap (`tempSwap`)**:
    - In this method, the two elements to be swapped are first stored in a temporary variable. The swapping process occurs in three steps:
        1. Store the first element in a temporary variable.
        2. Assign the second element to the first position.
        3. Assign the value from the temporary variable to the second position.

```javascript
    function tempSwap(array) {
        const length = array.length;
        const swap1 = Math.floor(Math.random() * length);
        const swap2 = Math.floor(Math.random() * length);
        const temp = array[swap1];
        array[swap1] = array[swap2];
        array[swap2] = temp;
    }
    ```

2. **Destructuring Swap (`destructuringSwap`)**:
    - This method leverages ES6 destructuring syntax to swap the elements without creating an explicit temporary variable. The swap is accomplished in one concise line using destructuring assignment:
        ```javascript
        function destructuringSwap(array) {
            const length = array.length;
            const swap1 = Math.floor(Math.random() * length);
            const swap2 = Math.floor(Math.random() * length);
            [array[swap1], array[swap2]] = [array[swap2], array[swap1]];
        }
        ```

### Pros and Cons

- **Temporary Variable Swap**:
    - **Pros**:
        - More universally compatible across different JavaScript versions and engines since it does not rely on newer syntax.
        - Clearer and more explicit in terms of what happens during the swap, which may aid readability for some developers.
    - **Cons**:
        - Slightly more verbose.
        - May involve minor performance hits due to the additional variable assignment, especially in larger datasets, though in many modern engines, this difference is negligible.

- **Destructuring Swap**:
    - **Pros**:
        - Concise and more readable once understood; reduces the number of lines of code.
        - Modern JavaScript engines might optimize destructuring more effectively, potentially leading to better performance.
    - **Cons**:
        - Relies on ES6+ features, which may not be compatible with very old JavaScript environments.
        - Because it’s a shorthand, it might be less clear to developers unfamiliar with destructuring syntax.

### Performance Observations from Test Results

From the benchmark results, the following observations can be made:

- For arrays of length 10:
    - Destructuring swap performs better than the temporary variable swap.
  
- For arrays of length 100:
    - The performance gap narrows, though destructuring still has an edge.

- For arrays of length 1000:
    - Both methods show a significant drop in execution speed, but the destructuring method performs worse than when dealing with smaller arrays, suggesting some overhead might be introduced in larger datasets or due to the nature of the engine optimizations.

### Other Considerations

- **Browser and Version Compatibility**: The performance can vary depending on the JavaScript engine of the browser being used. The result gathered was specific to Chrome 135, and different browsers or even different versions might yield different performance metrics.

- **Function Overhead**: Both functions introduce some overhead due to the way they are called and how random indices are generated. If working with small arrays frequently, this setup might introduce inefficiencies that would not be noticeable in larger operations where the actual swapping takes longer than the overhead.

### Alternatives

1. **Loop-Based Swaps**: Using a loop to iterate through the array and swapping all elements could be considered for bulk operations.
2. **In-place Sort Algorithms**: If the goal is to sort rather than just swap, sorting algorithms may utilize different strategies that can minimize the need for swaps.
3. **Linked Lists**: For frequent insertions and deletions, using linked lists may be more efficient than an array, depending on the use case.
4. **Immutable Operations**: In functional programming styles, you might opt for immutable data structures, where you avoid mutating the original array altogether.

This benchmark provides valuable insight into how two common techniques to swap elements can be tested against one another, helping programmers choose the right method based on array size and compatibility needs.

Related benchmarks:

Array item swapping, destructuring vs temp variable (throwaway destructuring) (version: 1)

Array destructuring vs temp variable use in array item swapping

Comparing performance of: Length 10 temp swap vs Length 10 destructuring swap vs Length 100 temp swap vs Length 100 destructuring swap vs Length 1000 temp swap vs Length 1000 destructuring swap

Created: 12 days ago by: Guest

Jump to the latest result

Length 10 temp swap

Length 10 destructuring swap

Length 100 temp swap

Length 100 destructuring swap

Length 1000 temp swap

Length 1000 destructuring swap

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated 12 days ago):