Benchmark: iterator speed1 - MeasureThat.net

Script Preparation code:

var arr = new Array(5000).fill(1);

Tests:

for of
for(const a of arr){ console.log(a); }
for
for(var a = 0; a < arr.length; a++){ console.log(arr[a]); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for of
for

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

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

LLMs can make mistakes. Check important info.

Let's break down the provided JSON data and explain what's being tested in this JavaScript microbenchmark.

**Benchmark Definition**

The benchmark is defined by two scripts:

1. `Script Preparation Code`: This line creates an array of 5000 elements filled with the value 1: `var arr = new Array(5000).fill(1);`. This script is used to prepare the test environment.
2. `Html Preparation Code`: Since this is not set, it means that no HTML preparation code is required.

The benchmark definition doesn't specify a particular library or special JavaScript feature. However, we'll discuss other considerations and potential alternatives below.

**Test Cases**

There are two individual test cases:

1. **"for of"`**
	* Benchmark Definition: `for(const a of arr){ console.log(a); }`
	* Purpose: This test case is designed to measure the execution speed of the "for...of" loop, which is used to iterate over an array using a more concise syntax.
2. **"for"`**
	* Benchmark Definition: `for(var a = 0; a < arr.length; a++) { console.log(arr[a]); }`
	* Purpose: This test case measures the execution speed of the traditional "for" loop, which uses a variable to keep track of the iteration index.

**Comparison**

The two test cases compare the performance of the "for...of" loop and the traditional "for" loop. The results will indicate which loop is faster for this specific use case.

Pros and Cons:

* **"For of"`**
	+ Pros: More concise syntax, potentially more readable code.
	+ Cons: May have slower execution speed due to the added overhead of iterating over an array using a custom iterator.
* **"For"`**
	+ Pros: Traditional loop that is widely understood and supported.
	+ Cons: Less concise syntax, may be less readable.

Other Considerations:

* The benchmark uses an array of 5000 elements, which can affect performance due to memory allocation and deallocation. A smaller array size might yield different results.
* The test cases don't account for potential optimizations that a real-world application would need to consider (e.g., caching, memoization).

**Library**

There is no explicitly mentioned library in the provided JSON data.

**Special JavaScript Feature or Syntax**

The "for...of" loop uses a custom iterator, which allows it to iterate over an array without accessing its indices directly. This syntax was introduced in ECMAScript 2015 (ES6) and provides a more concise way of iterating over arrays.

If you have any questions or would like further clarification, feel free to ask!

Related benchmarks:

iterator speed1 (version: 0)

Comparing performance of: for of vs for

Created: 3 years ago by: Guest

Jump to the latest result

for of

for

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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