Benchmark: arguments array vs declared arguments

Tests:

arguments
function foo() { return arguments[0] + arguments[1]; } var q = 0; for (var i = 0; i < 10000; i ++) { q += foo(i, i+1); } console.log(q);
direct
function foo(a, b) { return a + b; } var q = 0; for (var i = 0; i < 10000; i ++) { q += foo(i, i+1); } console.log(q);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
arguments
direct

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 28 days ago):

LLMs can make mistakes. Check important info.

Let's break down what's being tested in this benchmark.

**Benchmark Definition**

The benchmark is comparing two approaches to calling a function with variable arguments: using the `arguments` object and declaring the arguments explicitly.

**Options Compared**

There are two options being compared:

1. **Arguments Object**: This approach uses the built-in `arguments` object, which is an array-like object that contains all the arguments passed to a function.
2. **Declared Arguments**: In this approach, the arguments are declared explicitly as separate variables inside the function signature.

**Pros and Cons**

* **Arguments Object**:
	+ Pros: Simple to use, no need to declare additional variables.
	+ Cons: Can be slower due to array indexing operations, may lead to unexpected behavior if not used carefully (e.g., using `arguments[0]` instead of `a`).
* **Declared Arguments**:
	+ Pros: Generally faster, more predictable behavior, and easier to debug.
	+ Cons: Requires declaring additional variables, which can add clutter to the code.

**Library/Language Features**

There are no libraries or special language features being tested in this benchmark. However, it's worth noting that the use of `arguments[0]` instead of `a` is a common pattern in JavaScript, and using declared arguments is considered better practice by many developers.

**Other Considerations**

When deciding between these two approaches, consider the following:

* Performance: If speed is critical, declaring arguments might be a better choice.
* Code readability and maintainability: Declaring arguments can make code easier to understand and debug.
* Code complexity: Using `arguments` objects can add complexity due to potential issues with array indexing.

**Alternatives**

Other alternatives for handling variable arguments in JavaScript include:

* Using rest parameters (`...args`) introduced in ECMAScript 2015 (ES6+).
* Using destructuring assignment (`[a, b] = [i, i + 1]`).

The `rest parameters` approach is generally considered more elegant and efficient than the `arguments` object or declared arguments. However, it requires support for ES6+ syntax.

I hope this explanation helps you understand what's being tested in this benchmark!

Latest run results:

Run details: (Test run date: 6 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.77 Safari/537.36

Browser/OS: Chrome 70 on Windows

View result in a separate tab

Test name	Executions per second
arguments	19941.3 Ops/sec
direct	20035.0 Ops/sec

Related benchmarks:

arguments array vs declared arguments (version: 0)

Comparing performance of: arguments vs direct

Created: 6 years ago by: Guest

Jump to the latest result

arguments

direct

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 28 days ago):