Benchmark: forEach vs map, jolley style!

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Tests:

forEach
const arr = _.range(0,10000) arr.forEach(x => arr[x] = x * 2) console.log(arr)
map
const arr = _.range(0,10000) const newArr = arr.map(x => x * 2) console.log(newArr)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
forEach
map

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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I'd be happy to explain the provided benchmark.

**Benchmark Overview**

The benchmark is comparing two approaches: `forEach` and `map`, with Jolly style, which uses Lodash library. The purpose of this benchmark is to measure the performance difference between these two methods in a specific scenario.

**Options Compared**

Two options are compared:

1. **`forEach`**: This approach iterates over an array using a callback function, applying the transformation to each element directly.
2. **`map`**: This approach creates a new array by transforming each element of the original array using a callback function, without modifying the original array.

**Pros and Cons**

**`forEach` Approach:**

Pros:

* Simple and straightforward implementation
* No need to create a new array

Cons:

* May lead to more memory allocations and garbage collection due to direct modification of elements in the array.
* Potential for slower performance due to the callback function invocation overhead.

**`map` Approach:**

Pros:

* More efficient, as it avoids direct modifications of elements and creates a new array with transformed values.
* Can take advantage of JavaScript's optimizations for array operations.

Cons:

* Requires creating a new array, which can be memory-intensive.
* May lead to slower performance if the transformation is complex or computationally expensive.

**Lodash Library**

In this benchmark, Lodash is used to provide a convenient way to create an array with a range of values. Specifically, `_range` function generates an array from 0 to a specified upper bound.

**Other Considerations**

* The benchmark uses Chrome 79 as the test browser.
* The test is run on a desktop device running Windows.
* The results are measured in executions per second (EPS), which can provide insight into the performance difference between the two approaches.

**Alternatives**

For those interested in exploring alternative approaches, here are some options:

1. **`reduce`**: Another array method that can be used to transform elements, but it's typically less efficient than `map`.
2. **Manual iteration using a loop**: A more low-level approach that involves explicit looping and element access, which can be slower due to overhead.
3. **Other libraries or frameworks**: Depending on the specific use case, other libraries like Ramda or functional programming frameworks might offer alternative approaches for array transformations.

Keep in mind that performance differences between these methods can vary depending on the specific context, browser version, and hardware configuration.

Related benchmarks:

forEach vs map, jolley style! (version: 0)

Comparing performance of: forEach vs map

Created: 6 years ago by: Guest

Jump to the latest result

forEach

map

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):