Benchmark: ak;ldjf;lakdjf - MeasureThat.net

Script Preparation code:

function generateTestArray() {
  const result = [];
  for (let i = 0; i < 1000000; ++i) {
    result.push({
      a: i,
      b: i / 2,
      r: 0,
    });
  }
  return result;
}

Tests:

spread
const array = generateTestArray(); const newMap = new Map(array); const foo = [...newMap.entries()];
from
const array = generateTestArray(); const newMap = new Map(array); const foo = Array.from(newMap.entries());

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
spread
from

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.3 Safari/605.1.15

Browser/OS: Safari 16 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
spread	26.3 Ops/sec
from	26.2 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of MeasureThat.net and explore what's being tested in this benchmark.

**Benchmark Purpose**

The purpose of this benchmark is to compare the performance of two approaches: using `Array.from()` and using the spread operator (`...`) to convert an array to a new array with entries. The test case uses a large array of 1 million objects, which is generated by a custom JavaScript function `generateTestArray()`. This function creates an array of objects with properties `a`, `b`, and `r`.

**Approaches Compared**

There are two approaches being compared:

1. **Using `Array.from()`**: The benchmark checks the performance of converting the array to a new array using the `Array.from()` method.
2. **Using the spread operator (`...`)**: The benchmark also checks the performance of using the spread operator to convert the array to a new array with entries.

**Pros and Cons**

**Array.from()**

Pros:

* More explicit and readable way to create an array from a collection
* Can be used to create arrays from other types of collections, such as sets or maps

Cons:

* May incur additional overhead due to creating a new empty array and then copying the elements

**Spread Operator (`...`)**

Pros:

* Concise and expressive syntax
* Can be faster for large datasets since it avoids creating an intermediate array

Cons:

* Less explicit and less readable than `Array.from()`
* Only works with arrays, not other types of collections

**Other Considerations**

Both approaches have their trade-offs. Using `Array.from()` can provide more control and flexibility, but may incur additional overhead. The spread operator is concise and expressive, but its performance benefits come at the cost of readability.

**Library Usage**

In this benchmark, no external libraries are used. However, it's worth noting that some JavaScript engines may have built-in optimizations or features that could affect the results.

**Special JS Features or Syntax**

This benchmark does not use any special JavaScript features or syntax beyond the standard ECMAScript specification.

**Alternatives**

If you're looking for alternative approaches to convert an array to a new array with entries, here are a few options:

* Using `Array.prototype.map()`: This method returns a new array with the results of applying a provided function on every element in the original array.
* Using `slice()` and then applying `map()` or other methods: This approach involves creating a copy of the array using `slice()`, and then applying another method to convert it to a new array with entries.

Keep in mind that these alternatives may have different performance characteristics compared to `Array.from()` and the spread operator.

Related benchmarks:

ak;ldjf;lakdjf (version: 0)

Comparing performance of: spread vs from

Created: one year ago by: Guest

Jump to the latest result

spread

from

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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