Benchmark: map vs foreach 38947593845

Script Preparation code:

var replacementTags = ['A', 'b', 'C'];
var customLocalTags = [];

Tests:

map
customLocalTags = replacementTags.map((tag) => { return { value: tag, name: tag }; });
foreach
replacementTags.map((tag) => { customLocalTags.push({ value: tag, name: tag }); });

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
map
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):

LLMs can make mistakes. Check important info.

I'd be happy to explain the provided benchmark.

The benchmark is testing two approaches for iterating over an array in JavaScript: `map` and `forEach`. The test cases are designed to measure which approach performs better in terms of speed.

**Approach 1: Map**

In this approach, the `map()` function is used to create a new array with the results of applying a provided function to each element in the original array. In this case, the function creates an object with two properties: `value` and `name`, which are set to the same value as the input tag.

**Approach 2: Foreach**

In this approach, the `forEach()` function is used to iterate over the elements of the original array. The function pushes a new object into the `customLocalTags` array for each element in the `replacementTags` array.

Now, let's discuss the pros and cons of these approaches:

**Map:**

Pros:

* Creates a new array with the results, which can be useful if you need to perform further operations on the resulting data.
* Can be more expressive and concise than using a loop or `forEach()`.

Cons:

* Creates a new array in memory, which can be inefficient for large datasets.
* Can be slower than using a loop or `forEach()` if the function is computationally expensive.

**Foreach:**

Pros:

* Does not create a new array in memory, making it more efficient for large datasets.
* Can be faster than using `map()` if the function is computationally expensive.

Cons:

* Requires pushing elements into an existing array, which can be slower than creating a new array with `map()`.
* Can make the code less expressive and more verbose.

Other considerations:

* The benchmark uses Chrome 80 as the test browser. Different browsers may have different performance characteristics for these approaches.
* The benchmark runs on a desktop device, which may affect performance compared to running on mobile devices or other platforms.
* The `customLocalTags` array is used as a reference point for both approaches, but it's not clear if this affects the results.

**Library/Function usage:**

The benchmark uses the following JavaScript functions:

* `map()`: A built-in function that creates a new array with the results of applying a provided function to each element in the original array.
* `forEach()`: A built-in function that executes a callback function for each element in an array.

**Special JS feature/syntax:**

This benchmark does not mention any special JavaScript features or syntax. It's a simple comparison of two approaches using built-in functions.

**Alternatives:**

If you need to measure the performance of other iteration methods, such as:

* Loops (e.g., `for` loops)
* Array.prototype.reduce()
* Array.prototype.every() and Array.prototype.some()

you can create additional test cases to compare these approaches.

Related benchmarks:

map vs foreach 38947593845 (version: 0)

Comparing performance of: map vs foreach

Created: 6 years ago by: Guest

Jump to the latest result

map

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):