Benchmark: best array generator

Tests:

for loop
const arr = []; for (i=0; i <= 1E5; i++) arr[i] = i;
for loop with push
const arr = []; for (i=0; i <= 1E5; i++) arr.push(i);
spread syntax
const arr = [...Array(1E5).keys()]

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for loop
for loop with push
spread syntax

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/109.0.0.0 Safari/537.36

Browser/OS: Chrome 109 on Linux

View result in a separate tab

Test name	Executions per second
for loop	1144.0 Ops/sec
for loop with push	1208.1 Ops/sec
spread syntax	373.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks.

**What is being tested?**

MeasureThat.net is testing three different approaches to generate an array in JavaScript: a traditional `for` loop, a `for` loop with the `push()` method, and the spread syntax (`...Array(1E5).keys()`).

The goal is to determine which approach generates an array the fastest.

**Options being compared**

We have three options being compared:

1. **Traditional `for` loop**: This approach uses a traditional `for` loop with an index variable `i`, incrementing it on each iteration, and assigning the current value of `i` to an element in the array.
2. **`for` loop with push()**: This approach also uses a `for` loop, but instead of assigning values directly to elements, it uses the `push()` method to add new elements to the end of the array.
3. **Spread syntax**: This approach uses the spread syntax (`...Array(1E5).keys()`) to create an array with 100,000 elements.

**Pros and cons of each approach**

1. **Traditional `for` loop**:
	* Pros: Simple and straightforward, easy to understand and maintain.
	* Cons: May be slower due to the overhead of incrementing a variable and assigning values directly to elements.
2. **`for` loop with push()**:
	* Pros: Similar to traditional loops, but avoids direct assignment, which can improve performance.
	* Cons: Requires using `push()` method, which may introduce additional overhead.
3. **Spread syntax**:
	* Pros: Convenient and concise, eliminates the need for manual indexing.
	* Cons: May be slower due to the creation of a new array object and iteration over its indices.

**Library and special JS feature**

There are no libraries or special JavaScript features being used in these benchmarks.

**Other alternatives**

If we were to consider alternative approaches to generating an array, some other options might include:

1. `Array.from()`: This method creates a new array from an iterable (e.g., an array expression).
2. Destructuring assignment: This syntax allows assigning values directly from an iterable or array.

However, these alternatives are not being compared in the provided benchmark.

In summary, MeasureThat.net is testing three approaches to generate an array in JavaScript: traditional `for` loops, `for` loops with `push()`, and the spread syntax. Each approach has its pros and cons, and understanding these differences can help optimize performance-critical code.

Related benchmarks:

best array generator (version: 0)

Comparing performance of: for loop vs for loop with push vs spread syntax

Created: one year ago by: Guest

Jump to the latest result

for loop

for loop with push

spread syntax

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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