Benchmark: for const comparison

Script Preparation code:

var people = [{name: 'a', age:1}, {name: 'a', age:1}, {name: 'a', age:1}, {name: 'a', age:1}, {name: 'a', age:1}, {name: 'a', age:1}, {name: 'a', age:1}, {name: 'a', age:1}, {name: 'a', age:1}, {name: 'a', age:1}, {name: 'a', age:1}, {name: 'a', age:1}]

Tests:

with const
const peopleWork = []; for (const p of people){ peopleWork.push(p); }
simple for
const peopleWork = []; for (p of people){ peopleWork.push(p); }
forEach
const peopleWork = []; people.forEach((p) => { peopleWork.push(p); });

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
with const
simple for
forEach

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36

Browser/OS: Chrome 123 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
with const	16617028.0 Ops/sec
simple for	640163.6 Ops/sec
forEach	13735197.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

**Benchmark Definition JSON**

The provided JSON represents a benchmark definition, which is a script that defines a test scenario. In this case, we have three benchmark definitions:

1. "for const comparison"
2. "with const"
3. "simple for"

The benchmark definition for "for const comparison" creates an array `people` with 12 elements and then uses a `for` loop to iterate over the array, pushing each element onto another array `peopleWork`. This is repeated three times.

The other two benchmark definitions ("with const" and "simple for") are similar, but with slight variations:

* "with const": Uses a `const` declaration for the variable `p`, which means that the variable is declared but not reassigned.
* "simple for": Does not use the `const` keyword.

**What's being tested?**

The benchmark is testing the performance of three different ways to iterate over an array in JavaScript:

1. A traditional `for` loop with a variable declaration (not using `const`).
2. An iterative approach using a `forEach` method.
3. An iterative approach using a `const` variable.

**Options compared**

The benchmark is comparing the performance of these three approaches:

* Traditional `for` loop
* `forEach` method
* Using `const` for variable declaration

**Pros and Cons**

Here's a brief overview of the pros and cons of each approach:

1. **Traditional `for` loop**: This is a straightforward way to iterate over an array, but it can be slower than other approaches due to the overhead of declaring a new variable.
	* Pros: Easy to understand and implement.
	* Cons: Can be slower due to variable declaration overhead.
2. **forEach** method: This approach uses a callback function to process each element in the array.
	* Pros: Can be faster than traditional `for` loops, as it avoids declaring a new variable.
	* Cons: May have performance issues if the callback function is complex or expensive to execute.
3. **Using `const` for variable declaration**: This approach uses a `const` variable to iterate over the array, which can help avoid variable hoisting issues.
	* Pros: Can improve performance by avoiding variable declaration overhead.
	* Cons: May not be compatible with older JavaScript versions that don't support `const`.

**Library and special JS features**

The benchmark definitions use the following libraries:

* None explicitly, but the `forEach` method is a built-in Array method in modern JavaScript.

No special JavaScript features are used in these benchmark definitions. They only focus on testing basic iteration approaches.

**Other alternatives**

If you were to extend this benchmark, you could consider adding more variations, such as:

* Using `for...of` loops instead of traditional `for` loops
* Adding array elements with complex properties or expensive operations
* Testing performance in different JavaScript environments (e.g., Node.js, WebKit)

Keep in mind that the goal of a benchmark is to measure the performance of specific code patterns, so it's essential to keep the variations focused and relevant to the test scenario.

Related benchmarks:

for const comparison (version: 0)

Comparing performance of: with const vs simple for vs forEach

Created: 2 years ago by: Guest

Jump to the latest result

with const

simple for

forEach

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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