Benchmark: moawnaibwnuavwbtvwt

Script Preparation code:

var arr = new Array(15000);
arr.fill({ id: 0 });
arr = arr.map((el, idx) => el.id = idx);
var foo = arr[arr.length-1];

Tests:

findIndex
arr.findIndex((itm) => itm.id === foo);
for loop
for (let i = 0; i < arr.length; i++) { if (arr[i].id === foo) break; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
findIndex
for loop

Fastest: N/A

Slowest: N/A

Latest run results:

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

LLMs can make mistakes. Check important info.

Let's break down the provided JSON benchmark definition and test cases.

**Benchmark Definition**

The main task of this benchmark is to compare the performance of two approaches for finding an object in an array: using `findIndex` with a callback function, and a traditional `for` loop. The array contains 15,000 elements, each with an `id` property set to its index.

**Script Preparation Code**

The script preparation code generates the array:

```javascript
var arr = new Array(15000);
arr.fill({ id: 0 });
arr = arr.map((el, idx) => el.id = idx);
var foo = arr[arr.length-1];
```

Here's what each line does:

* `new Array(15000)` creates an array with 15,000 elements.
* `arr.fill({ id: 0 })` sets the initial value of all elements to an object with `id` property set to 0.
* `arr = arr.map((el, idx) => el.id = idx)` updates each element's `id` property to its original index. This is done using the `map()` method and a callback function that assigns the new value to the element.
* `var foo = arr[arr.length-1]` sets a variable `foo` to the last element of the array.

**Html Preparation Code**

Since this benchmark only uses JavaScript, there's no HTML preparation code.

**Library Usage**

There is no explicit library usage in the script preparation code. However, it's worth noting that the `map()` method and the callback function used in `findIndex` are part of the ECMAScript standard, which means they're implemented natively by most browsers.

**Special JavaScript Features/Syntax**

The benchmark uses a few features:

* The spread operator (`...`) in the `map()` callback is available from ECMAScript 2015 (ES6) onwards.
* The arrow function syntax (`(el, idx) => el.id = idx`) is also part of ES6.
* The `fill()` method was introduced in ES5.

**Performance Comparison**

The benchmark compares two approaches:

1. Using `findIndex` with a callback function:
```javascript
arr.findIndex((itm) => itm.id === foo);
```

This approach uses the `findIndex()` method, which returns the index of the first element that satisfies the condition (in this case, finding an element with `id` property equal to the value of `foo`). If no such element is found, it returns -1.

2. A traditional `for` loop:
```javascript
for (let i = 0; i < arr.length; i++) {
  if (arr[i].id === foo) break;
}
```

This approach uses a traditional `for` loop to iterate through the array and checks each element's `id` property until it finds a match.

**Pros and Cons**

Here are some pros and cons of each approach:

1. **FindIndex**:
	* Pros:
		+ More concise and expressive code.
		+ Can be faster for large arrays, as it only iterates through the array until finding a match.
	* Cons:
		+ May have performance issues if the array is very large, as it has to iterate through the entire array.
2. **For Loop**:
	* Pros:
		+ More control over the iteration process (e.g., breaking out of the loop early).
		+ Can be more efficient for small arrays or when exact indexing is required.
	* Cons:
		+ Less concise and expressive code.
		+ May be slower for large arrays, as it has to iterate through every element.

**Other Alternatives**

If you need to find an object in a large array, other approaches might include:

1. `forEach()` with a callback function that returns early when the desired element is found.
2. Using `Array.prototype.some()` or `Array.prototype.every()`, which can be more efficient than `findIndex()` for certain use cases.

Keep in mind that the best approach will depend on your specific requirements and performance constraints.

Related benchmarks:

moawnaibwnuavwbtvwt (version: 0)

Testing finding an object array via findIndex or by using a for loop

Comparing performance of: findIndex vs for loop

Created: 4 years ago by: Guest

Jump to the latest result

findIndex

for loop

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):