Benchmark: Spread operator vs. slice small real

Tests:

Spread operator
var n = []; while(true) { n.push('asdf'); n = [...n]; if(n.length >= 10000) break; }
Slice()
var n = []; while(true) { n.push('asdf'); n = n.slice(); if(n.length >= 10000) break; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Spread operator
Slice()

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what is being tested.

**Benchmark Overview**

The test compares two approaches to create a new array reference: using the spread operator (`[...]`) and using `slice()`. The goal is to determine which approach is faster for creating a large array of 10,000 elements.

**Options Compared**

There are only two options compared in this benchmark:

1. **Spread Operator (`[...]`)**: This creates a new array reference by spreading the elements of an existing array.
2. **Slice()**: This returns a shallow copy of a portion of an array.

**Pros and Cons**

* **Spread Operator (`[...]`)**:
	+ Pros: More concise, can be used to create arrays with dynamic sizes.
	+ Cons: May have performance overhead due to the creation of a new array reference.
* **Slice()**:
	+ Pros: Can be used to create arrays with specific ranges or offsets.
	+ Cons: Requires specifying the start and end indices, which can make it less convenient for creating large arrays.

**Library/ Framework**

Neither of the options in this benchmark uses any external library or framework. The test is primarily focused on comparing the performance of these two built-in JavaScript operators.

**Special JS Feature/Syntax**

There are no special features or syntax used in this benchmark that would require knowledge beyond basic JavaScript programming.

**Other Alternatives**

If you wanted to create a large array using other methods, some alternatives could include:

* Using `Array.from()` with an iterable source (e.g., an array of promises)
* Using `concat()` to concatenate multiple arrays
* Using a loop to push elements onto an existing array

However, these alternatives are not relevant to the specific benchmark being compared.

Overall, this benchmark provides a simple and concise way to compare the performance of two built-in JavaScript operators: the spread operator and `slice()`.

Latest run results:

Run details: (Test run date: 5 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36 OPR/58.0.3135.132

Browser/OS: Opera 58 on Mac OS X 10.14.3

View result in a separate tab

Test name	Executions per second
Spread operator	0.7 Ops/sec
Slice()	11.1 Ops/sec

Related benchmarks:

Spread operator vs. slice small real (version: 0)

Creating a "new" array reference every time

Comparing performance of: Spread operator vs Slice()

Created: 5 years ago by: Guest

Jump to the latest result

Spread operator

Slice()

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):