Benchmark: arrow vs inline function

Tests:

arrow
let r1 = 1; let k = () => { r1 = r1 ^ r1; }; k();
reg
let r1 = 1; function k() { r1 = r1 ^ r1; }; k();
const
let r1 = 1; const k = () => { r1 = r1 ^ r1; }; k();

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
arrow
reg
const

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0.0.0 Safari/537.36

Browser/OS: Chrome 130 on Windows

View result in a separate tab

Test name	Executions per second
arrow	114348952.0 Ops/sec
reg	110564680.0 Ops/sec
const	109297136.0 Ops/sec

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

LLMs can make mistakes. Check important info.

**Overview**

The provided JSON represents a JavaScript microbenchmarking test case, where the focus is on comparing the performance of three different function declaration approaches: arrow functions (`=>`), inline functions (i.e., traditional function declarations without an explicit return type), and constant expressions with function declarations. The benchmark aims to determine which approach provides better performance.

**Benchmarked Options**

The benchmark compares three options:

1. **Arrow Function**: Uses the `=>` syntax to declare a function that can be defined inline.
2. **Inline Function (Reg)**: Uses traditional function declarations without an explicit return type, similar to arrow functions but with a semicolon (`;`) at the end.
3. **Constant Expression with Function Declaration**: Uses a constant expression with a function declaration using the `const` keyword.

**Pros and Cons of Each Approach**

1. **Arrow Function**:
	* Pros: Expressive syntax, concise code, and can be used as a shorthand for small functions.
	* Cons: May have slower performance due to the overhead of the implicit return type lookup.
2. **Inline Function (Reg)**:
	* Pros: Performance-optimized since the return type is explicitly declared, and the compiler can optimize for it better.
	* Cons: Less expressive syntax than arrow functions, and may require more semicolons (`;`) to define inline functions.
3. **Constant Expression with Function Declaration**:
	* Pros: Can provide performance benefits by avoiding the overhead of function declarations.
	* Cons: Requires a `const` keyword to ensure that the variable is not reassigned after its declaration.

**Library**

There is no explicit library mentioned in the provided JSON. However, since the benchmark involves JavaScript functions, it's likely using the built-in JavaScript language features and does not rely on external libraries for performance measurements.

**Special JS Features or Syntax**

The benchmark uses the following special JavaScript feature:

* **Arrow Function**: The `=>` syntax is used to declare arrow functions.
* **Constant Expression with Function Declaration**: The `const` keyword is used to ensure that the variable is not reassigned after its declaration.

No other special features or syntax are mentioned in the provided JSON.

**Other Alternatives**

To optimize JavaScript function performance, developers may consider using:

1. **Caching mechanisms**, such as memoization or caching libraries like LRU Cache.
2. **Just-In-Time (JIT) compilation**, which can improve performance by compiling frequently executed functions at runtime.
3. **Async/await** and **Promise chaining**, which can simplify asynchronous code and potentially reduce execution time.

However, for a simple benchmark like this one, the differences between these approaches are likely to be relatively small, and the focus is on illustrating the basic concept of comparing different JavaScript function declaration approaches.

Related benchmarks:

arrow vs inline function (version: 0)

Comparing performance of: arrow vs reg vs const

Created: 4 years ago by: Guest

Jump to the latest result

arrow

reg

const

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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