Benchmark: Inline anonymous classes

Script Preparation code:

class PredefinedError extends Error {
  foo = 5;
  bar = "foo";
}

function throwShared() {
  throw new PredefinedError("Error message");
}

function throwAnon() {
  throw new class extends Error {
    foo = 5;
    bar = "foo";
  }("Error message");
}

function throwExtended() {
  throw Object.assign(new Error("Error message"), {
    foo: 5,
    bar: "foo",
  });
}

Tests:

Anonymous redefined class
let x = 0; try { throwAnon(); } catch(e) { x += e.foo; }
Predefined shared class
let x = 0; try { throwShared(); } catch(e) { x += e.foo; }
Builtin error with assigned properties
let x = 0; try { throwExtended(); } catch(e) { x += e.foo; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Anonymous redefined class
Predefined shared class
Builtin error with assigned properties

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/108.0.0.0 Safari/537.36

Browser/OS: Chrome 108 on Windows 7

View result in a separate tab

Test name	Executions per second
Anonymous redefined class	30122.4 Ops/sec
Predefined shared class	69363.8 Ops/sec
Builtin error with assigned properties	61794.2 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.

**Benchmark Definition JSON**

The provided JSON represents a benchmark that tests three different approaches for throwing errors in JavaScript:

1. **Predefined shared class**: `throwShared()`
2. **Anonymous redefined class**: `throwAnon()`
3. **Builtin error with assigned properties**: `throwExtended()`

All three approaches aim to throw an error object with two properties: `foo` and `bar`. The benchmark code uses a predefined error class (`PredefinedError`) for the shared class approach, while the anonymous redefined class and builtin error approaches use built-in JavaScript classes and objects.

**Options Compared**

The options being compared are:

1. **Predefined shared class**: Using a separate class to define the error object.
2. **Anonymous redefined class**: Defining an anonymous inner class to create the error object on-the-fly.
3. **Builtin error with assigned properties**: Using built-in JavaScript classes and objects (e.g., `Error`) to create the error object.

**Pros and Cons of Each Approach**

1. **Predefined shared class**:
	* Pros: Can be more readable and maintainable, especially for complex error objects.
	* Cons: Requires additional code and maintenance overhead, as the class needs to be defined separately.
2. **Anonymous redefined class**:
	* Pros: Can be more concise and efficient, as it avoids the need for a separate class definition.
	* Cons: May be less readable and maintainable, especially for complex error objects.
3. **Builtin error with assigned properties**:
	* Pros: Very concise and efficient, as it uses built-in JavaScript classes and objects.
	* Cons: Can lead to tight coupling between the error object's properties and the surrounding code.

**Library Usage**

None of the benchmark approaches use external libraries or frameworks.

**Special JS Features/Syntax**

The benchmark does not explicitly use any special JavaScript features or syntax beyond standard ECMAScript 2022. However, it relies on some built-in JavaScript features, such as:

* Classes (ECMAScript 2015)
* Error objects and classes
* Try-catch blocks

If you're interested in exploring other special JS features/syntax, please let me know!

**Other Alternatives**

Some alternative approaches to throwing errors in JavaScript include:

1. Using a custom error function (e.g., `throw new MyError('Error message')`)
2. Creating an error object using the `Object.create()` method and extending it with properties
3. Utilizing modern JavaScript features like destructuring or async/await for error handling

However, these approaches are not covered in this specific benchmark.

I hope this explanation helps you understand the benchmarks being discussed!

Related benchmarks:

Inline anonymous classes (version: 0)

https://es.discourse.group/t/error-detail/1857/49

Comparing performance of: Anonymous redefined class vs Predefined shared class vs Builtin error with assigned properties

Created: 2 years ago by: Guest

Jump to the latest result

Anonymous redefined class

Predefined shared class

Builtin error with assigned properties

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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