Benchmark: splice or filter

HTML Preparation code:

<script>
    const array = ["first", "second", "third", "asdawd", "cxzcas", "ljjjln", "dfh93fsad9", "asdfeh5", "dsag442", "gdsgds", "fdsfrhdgr"];
</script>

Script Preparation code:

function spliceIt(array, elementIdx) {
    const newArr = [...array]
    newArr.splice(elementIdx, 1);
    return newArr;
}

function filterIt(array, elementIdx) {
    return array.filter((el, idx) => idx !== elementIdx);
}

Tests:

filter
filterIt(array, 5);
splice
spliceIt(array, 5);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
filter
splice

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0.0.0 Safari/537.36

Browser/OS: Chrome 130 on Windows

View result in a separate tab

Test name	Executions per second
filter	5728067.0 Ops/sec
splice	4843928.0 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated one month ago):

LLMs can make mistakes. Check important info.

The benchmark you've provided compares two approaches for removing elements from an array in JavaScript: using the `splice` method and using the `filter` method. Both methods are commonly used for modifying arrays, but they operate in different ways and have distinct implications for performance, readability, and mutability.

### Benchmark Explanation:

**Tested Options:**

1. **`spliceIt` Function:**
   - **Method:** `Array.prototype.splice()`
   - **Use Case:** The `splice` method modifies the original array by removing or replacing existing elements and/or adding new elements in place. In this benchmark, it is used to remove an element at a specific index.
   - **Implementation:** The function first creates a shallow copy of the original array (to prevent mutating it), removes one element at the specified index, and returns the new array.

2. **`filterIt` Function:**
   - **Method:** `Array.prototype.filter()`
   - **Use Case:** The `filter` method creates a new array with all elements that pass a test implemented by the provided function. Here, it removes an element by its index without modifying the original array.
   - **Implementation:** The function iterates over the original array and includes all elements except the one at the specified index.

### Pros and Cons:

#### Splice:
- **Pros:**
  - Offers a straightforward way to modify the array in place, which can be useful if mutation is desired or necessary.
  - Performance can be better in scenarios where the length of the array is small, or when modifying is preferable to creating new instances.
  
- **Cons:**
  - Mutates the original array if you don't create a shallow copy, which can lead to unintended side effects if the original array is used elsewhere.
  - Can be less readable compared to functional methods like `filter`, particularly for those unfamiliar with mutative operations.

#### Filter:
- **Pros:**
  - Non-mutating: It returns a new array without altering the original, promoting immutability, which is a preferred practice in functional programming paradigms.
  - Generally provides clearer intent, showing that you’re filtering elements rather than performing in-place modifications.

- **Cons:**
  - May use more memory since it creates a new array, which could be impactful for very large arrays or frequent usage.
  - Performance might be slower in cases with very large datasets owing to iteration through the entire array.

### Performance Comparison:

Based on the latest benchmark results:
- The `filter` method executed at about **5,728,067 executions per second**, while `splice` executed at about **4,843,928 executions per second**. This suggests that the `filter` method performed better in this particular test scenario.

### Other Considerations:

- **Array Size and Complexity:** Performance may vary depending on the size of the array and the specific element to remove. For example, removing an element from the beginning of a large array using `splice` might have a different performance profile than removing from the end.
- **Maintainability:** When choosing between these two approaches, consider the maintainability of the code. Non-mutating functions can reduce bugs related to state changes, especially in collaborative environments.
- **Compatibility:** Both methods are widely supported across all modern browsers, making them safe to use without concern for compatibility issues.

### Alternatives:
Besides `splice` and `filter`, there are other methods to remove elements from an array:

1. **Slice Method:**
   - You can use the `slice` method to create two slices of the array and concatenate them back together, effectively removing the specified element.
   - Example: 
     ```javascript
     const removeElementUsingSlice = (array, index) => {
         return [...array.slice(0, index), ...array.slice(index + 1)];
     };
     ```

2. **Using Spread Operator:**
   - Similar to the above slice method, you can construct a new array without the targeted index using the spread operator and destructuring.

3. **Using Libraries:**
   - Libraries like Lodash provide utility functions such as `_.without()` or `_.pullAt()` that can abstract and optimize the removal process with additional features.

By carefully evaluating these methods based on your specific needs—whether performance, immutability, or code readability—the appropriate approach can be determined.

Related benchmarks:

splice or filter (version: 1)

Comparing performance of: filter vs splice

Created: one month ago by: Guest

Jump to the latest result

filter

splice

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated one month ago):