Benchmark: Benchmark: flatMap vs reduce vs while vs foreach vs for of

Script Preparation code:

var n = Array.from(Array(1000).keys())

Tests:

flatMap
n.flatMap((x,i) => [++i,i++])
reduce
n.reduce((acc, cur) => [...acc, ++cur, cur++], [])
while
let res = [], i=0; while(n.length>i++) res.push(i, i);
foreach
let res = []; n.forEach((_,i) => res.push(i+1, i+1))
for
let res = []; for (let i = 0; i < n.length; i++) { res.push(i+1, i+1) }
for of
let res = []; for (const i of n) { res.push(i+1, i+1) }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
flatMap
reduce
while
foreach
for
for of

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 11 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/136.0.0.0 Safari/537.36

Browser/OS: Chrome 136 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
flatMap	42257.7 Ops/sec
reduce	1627.9 Ops/sec
while	274578.5 Ops/sec
foreach	325829.6 Ops/sec
for	282628.7 Ops/sec
for of	337899.1 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down what's being tested in the provided JSON benchmark.

**Benchmark Definition:**
The benchmark is comparing four different approaches to iterate over an array:

1. `flatMap`
2. `reduce`
3. `while` loop
4. `forEach` loop
5. `for...of` loop

Each of these approaches is being compared for performance, which means the test is measuring how fast each method can execute a specific code snippet.

**Options Compared:**

* `flatMap`: Flattens an array by mapping over it and concatenating the results.
* `reduce`: Accumulates values in an array by reducing them using a callback function.
* `while` loop: Uses a conditional statement to repeatedly execute a block of code.
* `forEach` loop: Iterates over an array using a callback function for each element.
* `for...of` loop: Iterates over an array using a more concise syntax.

**Pros and Cons of Each Approach:**

* `flatMap`: Pros:
	+ Can be faster due to reduced overhead from concatenation.
	+ More functional programming style.
	+ May be more readable in certain contexts. Cons:
	+ Can be less efficient for large arrays due to the mapping operation.
* `reduce`: Pros:
	+ Can be faster for reducing values in an array.
	+ More concise and expressive than traditional loops. Cons:
	+ May require more setup and understanding of callback functions.
	+ Not as intuitive for simple iteration tasks.
* `while` loop: Pros:
	+ Allows for manual control over the iteration process.
	+ Can be more efficient for specific use cases (e.g., looping until a condition is met).
	Cons:
	+ More verbose than other options.
	+ Requires explicit loop management.
* `forEach` loop: Pros:
	+ Concise and easy to read.
	+ Works with most modern browsers and environments. Cons:
	+ Less flexible than traditional loops.
	+ May have performance issues for very large arrays.
* `for...of` loop: Pros:
	+ More concise and expressive than traditional loops.
	+ Allows for more control over the iteration process.

**Library Usage:**
None of the test cases use any external libraries. The code snippets are self-contained and only rely on built-in JavaScript features.

**Special JS Features or Syntax:**
There is no special JavaScript feature or syntax being tested in this benchmark.

**Other Considerations:**

* Browser support: The benchmark is running on a Chrome mobile browser, which might have specific performance characteristics.
* Device platform: The test is running on an Android device, which could affect the results due to differences in hardware and software configuration.
* Environment: The benchmark is executed in a headless environment, which might not accurately reflect real-world use cases.

**Alternatives:**
Other alternatives for iterating over arrays include:

* Traditional `for` loops
* Array methods like `map()`, `filter()`, and `every()`
* Higher-order functions like `Array.prototype.reduce()` and `Array.prototype.every()`

Keep in mind that the choice of iteration method depends on the specific requirements of your use case.

Related benchmarks:

Benchmark: flatMap vs reduce vs while vs foreach vs for of (version: 5)

Comparing performance of: flatMap vs reduce vs while vs foreach vs for vs for of

Created: 4 years ago by: Registered User

Jump to the latest result

flatMap

reduce

while

foreach

for

for of

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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