Benchmark: Array loop vs foreach vs map[2]

Script Preparation code:

   var arr = [];
    for (var i = 0; i < 1000; i++) {
      arr[i] = i;
    }
  
    function someFn(i) {
      return i * 3 * 8;
    }

Tests:

foreach
arr.forEach(function (item){ someFn(item); })
for
var i = 0; var len = arr.length; for (; i < len; i += 1) { someFn(arr[i]); }
map
arr.map(item => someFn(item))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
foreach
for
map

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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

LLMs can make mistakes. Check important info.

**Benchmark Overview**

The provided JSON represents a microbenchmark on MeasurThat.net, which compares the performance of three different approaches: `Array.prototype.forEach()`, traditional `for` loop, and `Array.prototype.map()`.

**Approaches Compared**

1. **`Array.prototype.forEach()`**: This approach uses the built-in `forEach()` method to iterate over the array elements.
2. **Traditional `for` loop**: This approach uses a traditional `for` loop with an index variable to iterate over the array elements.
3. **`Array.prototype.map()`**: This approach uses the built-in `map()` method to create a new array by applying the provided function to each element.

**Pros and Cons of Each Approach**

1. **`Array.prototype.forEach()`**:
	* Pros: concise, readable, and maintainable code; efficient iteration.
	* Cons: slower performance compared to traditional `for` loop due to overhead of method call and function lookup.
2. **Traditional `for` loop**:
	* Pros: direct access to array elements, no overhead of method calls or function lookups.
	* Cons: verbose code, prone to errors if indexing is off.
3. **`Array.prototype.map()`**:
	* Pros: concise and readable code; efficient iteration similar to `forEach()`.
	* Cons: creates a new array, which can lead to increased memory usage.

**Library Used**

The benchmark does not use any external libraries.

**Special JS Features/Syntax**

There are no special JavaScript features or syntax used in this benchmark.

**Other Alternatives**

Alternative approaches could include:

1. **`Array.prototype.reduce()`**: This approach uses the `reduce()` method to iterate over the array elements, which can be a more concise alternative to traditional `for` loop.
2. **Generator functions**: Generator functions can provide a more efficient and elegant way to iterate over large datasets.
3. **Web Workers**: If the benchmark is intended for a server-side or long-running scenario, using Web Workers can offload computation to separate threads, improving performance.

**Benchmark Results**

The latest benchmark results show that:

* `Array.prototype.map()` performs the best with an execution rate of 7787.7158203125 executions per second.
* Traditional `for` loop comes in second with a lower execution rate of 4001.962890625 executions per second.
* `Array.prototype.forEach()` is the slowest with an execution rate of 7012.52783203125 executions per second.

These results suggest that using built-in array methods like `map()` and `forEach()` can be efficient for iterative operations, while traditional `for` loops may require more optimization or alternative approaches to achieve good performance.

Related benchmarks:

Array loop vs foreach vs map[2] (version: 0)

Comparing performance of: foreach vs for vs map

Created: 4 years ago by: Guest

Jump to the latest result

foreach

for

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):