Benchmark: findIndex vs forEach 2

Script Preparation code:

var arr = new Array(15000);
arr.fill({ id: 0 });
arr = arr.map((el, idx) => el.id = idx);
var foo = Math.floor(Math.random() * 15000);

Tests:

findIndex
arr.findIndex((itm) => itm.id === foo);
ForEach
arr.forEach((value) => { if (value.id === foo) { return; } });

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
findIndex
ForEach

Fastest: N/A

Slowest: N/A

Latest run results:

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

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**What is tested?**

The provided JSON represents two individual test cases that compare the performance of `Array.prototype.findIndex` and `Array.prototype.forEach` in finding an element with a specific property value (`foo`) within an array of 15,000 elements. The array is populated with objects having an `id` property initialized to incremental values from 0 to 14,999.

**Options compared**

Two approaches are being compared:

1. **FindIndex**: Uses the `findIndex` method to find the index of the first element in the array that satisfies the provided callback function.
2. **ForEach**: Uses the `forEach` method to iterate over the array and execute a callback function for each element.

**Pros and Cons:**

*   **FindIndex**:
    *   Pros: This approach can potentially be faster if the desired element is found early in the array, as it stops iterating as soon as it finds a match. It's also more concise and expressive than `forEach`.
    *   Cons: If the element is not found, `findIndex` returns `-1`, which might lead to unnecessary iterations in subsequent code.
*   **ForEach**:
    *   Pros: This approach iterates over the entire array even if it doesn't find a match, making it more predictable and less prone to false negatives. It also allows for early termination by returning from the callback function.
    *   Cons: The `forEach` loop may be slower due to the overhead of checking each element individually.

**Library and syntax considerations**

In this case, no external libraries are used, so we're relying on built-in JavaScript functionality.

There are no special JavaScript features or syntax being used in these benchmark definitions. They rely solely on standard JavaScript methods and variables.

**Alternatives:**

Some alternative approaches to finding an element in an array include:

*   Using `Array.prototype.includes` (introduced in ECMAScript 2019) for a more concise way of checking if an element exists within the array.
*   Employing iterative solutions, like using a for loop or a while loop, which might be faster but are less readable and less expressive.

Overall, the choice between `findIndex` and `forEach` depends on the specific use case and requirements. If you're sure that the desired element will be found early in the array and you want to take advantage of concise code, `findIndex` is a good choice. However, if you need to ensure that all elements are processed regardless of whether an exact match is found or not, `forEach` might be more suitable.

It's worth noting that these benchmark results should be taken as a general guideline for your specific use case and may vary depending on the actual execution context and other factors like hardware and optimization level.

Related benchmarks:

findIndex vs forEach 2 (version: 0)

Comparing performance of: findIndex vs ForEach

Created: 2 years ago by: Guest

Jump to the latest result

findIndex

ForEach

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):