Benchmark: list push vs splice, with objects

Script Preparation code:

l = {
    a: undefined,
    b: undefined,
    c: undefined,
    d: undefined,
    e: undefined,
    f: undefined,
    g: undefined,
    h: undefined,
    i: undefined,
    j: undefined,
    k: undefined,
    l: undefined,
    m: undefined,
    n: undefined,
    o: undefined,
    p: undefined,
    q: undefined,
    r: undefined,
    s: undefined,
    t: undefined,
    u: undefined,
    v: undefined,
    w: undefined,
    x: undefined,
    y: undefined,
    z: undefined
}

Tests:

append
a = Array(l); a.push(3);
splice
a = Array(l); a.splice(0,0,3);
reverse
a = Array(l); a.reverse().push(3); a.reverse();
concat
a = Array(l); a = [3].concat(a);
unshift
a = Array(l); a.unshift(3);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
append
splice
reverse
concat
unshift

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

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

LLMs can make mistakes. Check important info.

I'd be happy to explain what's being tested on the provided JSON and describe the options compared.

**Benchmark Overview**

The benchmark measures the performance of different array methods in JavaScript: `append`, `unshift`, `reverse`, `concat`, and `splice`. The test cases use a large, anonymous object `l` with 26 properties as an array initializer.

**Options Compared**

The benchmark compares the following options:

1. **Array initialization**: Creating a new array using the `Array()` constructor or an array literal (`[]`).
2. **Push vs Splice**: Using `push()` to append elements to the end of the array versus using `splice()` with the first argument set to 0 and the second argument set to the number of elements to insert.
3. **Reverse**: Reversing the array and then pushing or unshifting an element.
4. **Concat**: Concatenating a new array to the existing one using the `concat()` method.

**Pros and Cons**

Here's a brief overview of each option:

1. **Array initialization**:
	* Pros: Fast, efficient way to create an array.
	* Cons: Can be slower for large arrays if using `[]`.
2. **Push vs Splice**:
	* `push()`:
		+ Pros: Faster, more intuitive way to append elements.
		+ Cons: Only works on arrays and can be slower for small arrays.
	* `splice()`:
		+ Pros: More versatile method that allows inserting or removing elements.
		+ Cons: Can be slower due to the overhead of manipulating the array's length.
3. **Reverse**:
	* Pros: Reverses the array in place, which can be faster for large arrays.
	* Cons: Requires two reverse operations (push and pop), which can be slower than a single `push()` operation.
4. **Concat**:
	* Pros: Allows combining multiple arrays into one, but can be slow due to the overhead of creating new arrays.
	* Cons: Not ideal for large arrays or performance-critical applications.

**Library Usage**

None of the test cases use any external libraries. The benchmark only relies on built-in JavaScript features.

**Special JS Features or Syntax**

There are no special JS features or syntax used in this benchmark. However, it's worth noting that some of these methods may have different behavior in certain browsers or environments (e.g., `concat()` may work differently in older versions of Firefox).

**Alternatives**

If you're interested in exploring alternative approaches to array manipulation, consider the following:

* Using `Set` objects instead of arrays for fast lookup and insertion.
* Utilizing `Array.prototype.at()` method for safe indexing.
* Leveraging WebAssembly (WASM) or other optimized libraries for performance-critical applications.

Keep in mind that each approach has its trade-offs, and the best choice depends on the specific use case and requirements.

Related benchmarks:

list push vs splice, with objects (version: 0)

Comparing performance of: append vs splice vs reverse vs concat vs unshift

Created: 3 years ago by: Registered User

Jump to the latest result

append

splice

reverse

concat

unshift

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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