Benchmark: javascript loops with reduce 3

Tests:

foreach
const items = Array.from({length: 1000}, () => Math.floor(Math.random() * 40)); let index = 0; items.forEach(i => index++);
for-in
const items = Array.from({length: 1000}, () => Math.floor(Math.random() * 40)); let index = 0; for (let i in items) { index++; }
for-of
const items = Array.from({length: 1000}, () => Math.floor(Math.random() * 40)); let index = 0; for (let i of items) { index++; }
for
const items = Array.from({length: 1000}, () => Math.floor(Math.random() * 40)); let index = 0; for(let i = 0; i < items.length; ++i) { index++; }
optimized-for
const items = Array.from({length: 1000}, () => Math.floor(Math.random() * 40)); let index = 0; for(let i = items.length; i > 0; --i) { index++; }
reduce
const items = Array.from({length: 1000}, () => Math.floor(Math.random() * 40)); items.reduce((acc,value) => { acc.push(value); return acc; }, new Array());

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
foreach
for-in
for-of
for
optimized-for
reduce

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):

LLMs can make mistakes. Check important info.

**Overview of the Benchmark**

The provided JSON represents a JavaScript microbenchmark test case hosted on MeasureThat.net. The test compares the execution performance of six different approaches to iterate over an array: `foreach`, `for-in`, `for-of`, `for`, `optimized-for`, and `reduce`.

**Options Compared**

1. **`foreach`**: Iterates over an array using a traditional for loop.
2. **`for-in`**: Iterates over an array using the `in` operator, which returns a property name-value pair object.
3. **`for-of`**: Iterates over an array using the `of` operator, which is a new way to iterate over arrays introduced in ECMAScript 2015 (ES6).
4. **`for`**: A traditional for loop without an iterator or index variable.
5. **`optimized-for`**: An optimized for loop that iterates over an array by accessing its `length` property directly, reducing the number of iterations.
6. **`reduce`**: Uses the `Array.prototype.reduce()` method to accumulate values in an array.

**Pros and Cons**

1. **`foreach`**: Simple and straightforward, but may be slower due to the overhead of a traditional for loop.
2. **`for-in`**: May be slower due to the unnecessary iteration over property names, which can lead to unnecessary computations.
3. **`for-of`**: A modern and efficient way to iterate over arrays, with minimal overhead.
4. **`for`**: A simple and straightforward approach, but may be slower than `optimized-for`.
5. **`optimized-for`**: Optimized for performance, as it reduces the number of iterations by accessing `length` directly. However, it may be less readable due to its concise syntax.
6. **`reduce`**: A useful method for accumulating values in an array, but may incur additional overhead due to the function invocation.

**Library and Purpose**

None of the test cases use a library beyond standard JavaScript. The `Array.prototype.reduce()` method is used in one of the test cases, which is a built-in method provided by the ECMAScript standard.

**Special JS Feature or Syntax**

The `of` operator ( introduced in ES6) is used in two test cases (`for-of`) to iterate over an array. This is a new syntax introduced in modern JavaScript versions.

**Other Alternatives**

For iterating over arrays, other alternatives include:

* Using `forEach()` with a callback function
* Using `map()`, `filter()`, and `every()` methods for specific use cases

However, the original six approaches listed in the benchmark (foreach, for-in, for-of, for, optimized-for, and reduce) are commonly used and widely supported across different JavaScript implementations.

Latest run results:

Run details: (Test run date: 2 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36

Browser/OS: Chrome 127 on Windows

View result in a separate tab

Test name	Executions per second
foreach	5260.1 Ops/sec
for-in	5135.1 Ops/sec
for-of	5464.9 Ops/sec
for	5541.6 Ops/sec
optimized-for	5567.5 Ops/sec
reduce	5309.9 Ops/sec

Related benchmarks:

javascript loops with reduce 3 (version: 0)

Comparing performance of: foreach vs for-in vs for-of vs for vs optimized-for vs reduce

Created: 2 months ago by: Guest

Jump to the latest result

foreach

for-in

for-of

for

optimized-for

reduce

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):