Benchmark: Array loop vs foreach vs map (Small arrays)

Script Preparation code:

   var arr = [];
    for (var i = 0; i < 20; i++) {
      arr[i] = i;
    }
  
    function someFn(i) {
      return i * 3 + 8;
    }

Tests:

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

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:

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

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**Benchmark Overview**

MeasureThat.net is a website that allows users to create and run JavaScript microbenchmarks. The provided benchmark definition json represents a test case that compares the performance of three different approaches: `foreach`, `for` loop, and `map()` function.

**What's being tested?**

The benchmark tests the execution time of each approach on small arrays with 20 elements. The array is initialized with values from 0 to 19 using a `for` loop. A simple function `someFn(i)` is defined to take an integer value `i` and return its triple plus 8.

**Options compared**

Three options are compared:

1. `foreach`: Uses the `forEach()` method to iterate over the array.
2. `for`: Uses a traditional `for` loop to iterate over the array.
3. `map()`: Uses the `map()` function to create a new array with transformed values.

**Pros and Cons of each approach:**

1. `foreach`:
	* Pros: Concise syntax, easy to read and write.
	* Cons: May have performance overhead due to method call overhead.
2. `for` loop:
	* Pros: Fastest execution time (no method calls), easy to optimize.
	* Cons: More verbose syntax, may be harder to read for some developers.
3. `map()` function:
	* Pros: Flexible and expressive, can handle more complex transformations.
	* Cons: May have performance overhead due to function call overhead.

**Library and its purpose**

The `forEach` method is a built-in JavaScript method that iterates over an array and executes a callback function for each element. The `map()` function also iterates over an array and creates a new array with transformed values.

In the benchmark, both `foreach` and `map()` use these libraries to perform their respective operations on the input array.

**Special JS feature or syntax**

There is no special JS feature or syntax used in this benchmark. The code only uses standard JavaScript syntax and built-in functions.

**Other alternatives**

Alternative approaches could include:

* Using `reduce()` function instead of `forEach` or `map`.
* Using regular expressions to iterate over the array.
* Using a library like Lodash to perform operations on arrays.

However, these alternatives would likely change the focus of the benchmark and may not provide a fair comparison with the original three approaches.

Related benchmarks:

Array loop vs foreach vs map (Small arrays) (version: 0)

Comparing performance of: foreach vs for vs map

Created: 5 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):