Benchmark: splice vs reduce- move item to the end

Script Preparation code:

var list = [];
for (var i = 0; i < 5; i++) {
  list.push(i);
}
var startIndex = 0;
var endIndex = 4;

Tests:

splice
const result = Array.from(list); const [removed] = result.splice(startIndex, 1); result.splice(endIndex, 0, removed); return result;
reduce
const itemToMove = list[startIndex]; return list.reduce((acc, item, index) => { if (index === startIndex) { return acc; } if (index === endIndex) { return startIndex < endIndex ? [...acc, item, itemToMove] : [...acc, itemToMove, item]; } return [...acc, item]; }, []);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
splice
reduce

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.36

Browser/OS: Chrome 119 on Android

View result in a separate tab

Test name	Executions per second
splice	1991380.8 Ops/sec
reduce	694944.8 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what's being tested.

**Benchmark Description**

The benchmark is comparing two approaches to move an item from one position to another in an array:

1. `splice`: Using the `splice` method to remove and then insert the item at a specific index.
2. `reduce`: Using the `reduce` method to accumulate the items in the array, moving the item to the end.

**Options Compared**

The two options being compared are:

* `splice`: A built-in JavaScript method that modifies the original array by removing or inserting items at specific indices.
* `reduce`: A built-in JavaScript method that applies a function to each element of an array, accumulating a value.

**Pros and Cons of Each Approach**

**Splice:**

Pros:

* Efficient for small arrays (O(1) amortized time complexity)
* Simple to use

Cons:

* Modifies the original array
* Can be slower for large arrays due to the overhead of creating a new array

**Reduce:**

Pros:

* Flexible and can handle any type of data structure (not just arrays)
* Allows for easy accumulation of values

Cons:

* Typically slower than `splice` due to the overhead of applying a function to each element
* Requires more code to implement, especially for larger datasets

**Other Considerations**

Both approaches have their trade-offs. If you need to modify an array frequently and don't care about preserving the original data, `splice` might be a better choice. However, if you're working with large datasets or want to avoid modifying the original array, `reduce` could be a more suitable option.

**Library Usage**

None of the test cases use any external libraries beyond the built-in JavaScript methods (`splice` and `reduce`).

**Special JS Features/Syntax**

There are no special JavaScript features or syntax used in this benchmark. The code is straightforward and uses only standard JavaScript constructs.

**Alternative Approaches**

If you're interested in exploring alternative approaches, here are a few options:

* Using the `filter` method to create a new array with the item at the desired position.
* Using the `map` method to create a new array with modified elements.
* Implementing a custom iterative solution using loops and indexing.

Keep in mind that these alternatives might not be as efficient or straightforward as the `splice` and `reduce` methods, but they could provide insight into other ways of solving this problem.

Related benchmarks:

splice vs reduce- move item to the end (version: 0)

Comparing performance of: splice vs reduce

Created: one year ago by: Guest

Jump to the latest result

splice

reduce

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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