Benchmark: Array empty 2 - MeasureThat.net

Script Preparation code:

arr = []

Tests:

length == 0
if(arr.length === 0) {console.log("!")}
arr == []
if(arr === []) {console.log("!")}

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
length == 0
arr == []

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

I'll break down the provided JSON benchmark definition and explain what's being tested, compared, and other considerations.

**Benchmark Definition**

The test case defines two different ways to check if an array is empty:

1. `length == 0`: This checks if the length of the array is equal to zero.
2. `arr === []`: This directly compares the array with an empty array (`[]`).

Both tests use a simple JavaScript snippet that assigns an empty array to a variable named "arr" and then performs the respective check.

**Options Compared**

The benchmark compares two different approaches:

1. Using `length == 0`
2. Using `arr === []`

These two options are compared in terms of performance, as measured by the number of executions per second.

**Pros and Cons of Each Approach**

**Using `length == 0`**

Pros:

* This approach is a built-in JavaScript feature that is likely to be optimized by the engine.
* It's easy to understand and implement.

Cons:

* May not work correctly in all situations (e.g., if the array contains null or undefined elements).
* May incur additional overhead due to the length property being accessed.

**Using `arr === []`**

Pros:

* This approach is more explicit and easier to understand.
* Avoids potential issues with `length == 0`.

Cons:

* May not be optimized by the engine as much, since it's a direct comparison.
* Can be slower due to the unnecessary creation of an empty array object.

**Other Considerations**

1. **Null or Undefined Elements**: Both tests assume that the array only contains elements (not null or undefined). If the array may contain such elements, additional checks would be needed.
2. **Array Size**: The test case doesn't consider the impact of large array sizes on performance. In reality, accessing an array's length can have a significant impact on performance for large arrays.

**Library Usage**

There is no library usage in this benchmark definition.

**Special JS Features or Syntax**

None are mentioned explicitly.

**Alternatives**

Other alternatives to compare might include:

* Using `arr === null || arr === undefined`: This checks if the array is null or undefined, which may be a more comprehensive check.
* Using a loop to iterate over the array: This would ensure that all elements in the array are checked, but may be slower due to the additional overhead of iteration.
* Using a different data structure (e.g., Set): Depending on the requirements, using a Set might provide better performance for certain operations.

Keep in mind that these alternatives would require modifications to the benchmark definition and test cases.

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Ubuntu Chromium/79.0.3945.79 Chrome/79.0.3945.79 Safari/537.36

Browser/OS: Chromium 79 on Ubuntu

View result in a separate tab

Test name	Executions per second
length == 0	86436.2 Ops/sec
arr == []	5345823.0 Ops/sec

Related benchmarks:

Array empty 2 (version: 0)

Comparing performance of: length == 0 vs arr == []

Created: 4 years ago by: Guest

Jump to the latest result

length == 0

arr == []

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):