Benchmark: lodash forEach vs for i loop forof1

HTML Preparation code:

<script src="https://cdn.jsdelivr.net/lodash/4.16.0/lodash.min.js"></script>

Script Preparation code:

var values = [{
    a: 30310
}, {
    b: 100303
}, {
    c: 3040494
}]
var valArr = [];

for (let i = 0; i < 20000; i++) {
    valArr.push({
        a: 1,
        b: 2,
        c: 3
    });
}

Tests:

lodash.forEach
var count = 0; _.forEach(valArr, function(v) { if (v.a != null) { count++; } })
native
var count = 0; for (let v of valArr) { if (v.a != null) { count++; } }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lodash.forEach
native

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/84.0.4147.105 Safari/537.36

Browser/OS: Chrome 84 on Mac OS X 10.14.6

View result in a separate tab

Test name	Executions per second
lodash.forEach	2597.3 Ops/sec
native	23565.8 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided JSON and explain what is tested, compared options, pros and cons of each approach, and other considerations.

**Benchmark Definition**

The benchmark definition consists of two parts: `Script Preparation Code` and `Html Preparation Code`. The `Script Preparation Code` defines a JavaScript array `valArr` with 20,000 elements and an empty array `valArr` to be iterated over. It also initializes a counter variable `count`.

The `Html Preparation Code` includes the URL of the Lodash library, which is used in one of the benchmark test cases.

**Individual Test Cases**

There are two individual test cases:

1. **Lodash forEach**: This test case uses the `_` (underscore) object from the Lodash library to iterate over the `valArr` array using the `forEach` method. The code increments a counter variable `count` whenever an element's property `a` is not null.
2. **Native**: This test case uses a traditional `for...of` loop to iterate over the `valArr` array, incrementing the same counter variable `count` as in the Lodash `forEach` test case.

**Comparison**

The two test cases compare the performance of using a library (`Lodash`) versus a native JavaScript implementation (`Native`). The Lodash `forEach` method is expected to be slower than the native `for...of` loop due to the overhead of calling a function for each iteration, whereas the native approach avoids this overhead.

**Pros and Cons**

* **Lodash forEach**: Pros:
	+ Simplifies code by providing a concise way to iterate over arrays.
	+ Reduces boilerplate code.
Cons:
	+ Adds an external library dependency, which may introduce additional overhead or security risks.
	+ May be slower due to the function call overhead.
* **Native**: Pros:
	+ Faster execution, as it avoids the function call overhead.
	+ No external library dependency.
Cons:
	+ Requires manual loop logic, which can be error-prone and less readable.

**Other Considerations**

* The benchmark assumes that the Lodash library is already included in the browser or context, which may not always be the case. In a real-world scenario, you might need to include the library explicitly.
* The test cases do not account for other factors that can affect performance, such as:
	+ Array length and type
	+ Data distribution (e.g., random vs. sequential)
	+ Browser version and platform-specific optimizations

**Alternatives**

Other approaches to iterating over arrays in JavaScript include:

1. **Array.prototype.forEach**: A built-in method that is similar to Lodash's `forEach`, but without the need for an external library.
2. **Array.prototype.map() + Array.prototype.every()**: Combining `map()` and `every()` can provide a more efficient way to iterate over arrays, especially when filtering or transforming data.
3. **Custom loop implementations**: Implementing custom loops using `while` or `do-while` statements can be an alternative to the native `for...of` approach.

In summary, the benchmark highlights the trade-offs between using external libraries and native JavaScript implementation for array iteration. While Lodash's `forEach` provides a concise way to iterate over arrays, it may come at the cost of performance due to function call overhead. The native `for...of` loop, on the other hand, offers faster execution but requires manual loop logic and no external library dependency.

Related benchmarks:

lodash forEach vs for i loop forof1 (version: 0)

Comparing performance of: lodash.forEach vs native

Created: 4 years ago by: Guest

Jump to the latest result

lodash.forEach

native

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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