Benchmark: fn vs afn - MeasureThat.net

Script Preparation code:

var X = 0;
var A = function(V) {return X = V;};
var B = V => X = V;
var C = V => B(V);

Tests:

1
A(++X);
2
B(++X);
3
C(++X);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
1
2
3

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36

Browser/OS: Chrome 123 on Windows

View result in a separate tab

Test name	Executions per second
1	1733965.0 Ops/sec
2	1762211.6 Ops/sec
3	1438425.2 Ops/sec

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 and explain what's being tested.

**Benchmark Definition**

The benchmark is comparing three functions: `A`, `B`, and `C`. These functions are designed to test how JavaScript engine optimizes function calls with immediate function invocation (IFI) using the `++` operator.

Here's a brief explanation of each function:

* `A`: A traditional function declaration with an arrow function (`=>`) inside. The `V` parameter is assigned to the variable `X`, which is initialized outside the function.
* `B`: An arrow function that immediately assigns its argument `V` to the variable `X`.
* `C`: A function that calls `B` with its argument `V`, effectively doing the same thing as `A`.

**Options Compared**

The three functions are being compared in terms of performance. The options being tested are:

* Traditional function declaration (`A`)
* Arrow function (`B`)
* Function call with immediate function invocation using the `++` operator (`C`)

**Pros and Cons**

Here's a brief overview of each approach:

* **Traditional function declaration (A)**:
	+ Pros: Well-established syntax, easy to read and maintain.
	+ Cons: May result in slower execution due to overhead of function creation and lookup.
* **Arrow function (B)**:
	+ Pros: Concise syntax, reduces overhead compared to traditional function declarations.
	+ Cons: Limited compatibility with older browsers or environments that don't support arrow functions.
* **Function call with immediate function invocation using the `++` operator (C)**:
	+ Pros: Can be optimized by the JavaScript engine for inlining and caching, potentially leading to better performance.
	+ Cons: Unconventional syntax, may not be immediately clear to other developers.

**Library Used**

None of the provided functions use any external libraries.

**Special JS Features or Syntax**

The `++` operator is being used with function invocation, which is a special case in JavaScript. The `++` operator has different meanings depending on its context:

* In arithmetic expressions: increments a value.
* In loops: post-increment/decrement operators that modify the value after it's been read.

In this benchmark, the `++` operator is used to invoke the functions immediately, which is a common pattern in JavaScript. However, this syntax may not be familiar to all developers, and its meaning might take some time to grasp.

**Other Alternatives**

If you're interested in exploring alternative approaches or optimizing these functions further, consider the following:

* Use `function()` with the `this` context to create a new scope for each invocation.
* Experiment with techniques like tail call optimization (TCO) or loop unrolling to optimize the performance of these functions.
* Consider using a JavaScript profiling tool to identify potential bottlenecks in your application.

Keep in mind that optimizations should be done carefully, as they can affect code readability and maintainability. Always test and validate any changes before deploying them in production.

Related benchmarks:

fn vs afn (version: 0)

Comparing performance of: 1 vs 2 vs 3

Created: 2 years ago by: Guest

Jump to the latest result

1

2

3

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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