Benchmark: class with/without declared fields

Script Preparation code:

// classes declared here can't be accessed in test cases for some reason...

Tests:

class without declared fields
class X { constructor(foo, bar, baz) { this.foo = foo; this.bar = bar; this.baz = baz; } sum() { return this.foo + this.bar + this.baz; } } let i = 1000; let y = 0; while (i--) { let x = new X(1, 2, 3); y += x.foo + x.bar + x.baz; y += x.sum(); } return y;
class with declared fields
class X { foo; bar; baz; constructor(foo, bar, baz) { this.foo = foo; this.bar = bar; this.baz = baz; } sum() { return this.foo + this.bar + this.baz; } } let i = 1000; let y = 0; while (i--) { let x = new X(1, 2, 3); y += x.foo + x.bar + x.baz; y += x.sum(); } return y;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
class without declared fields
class with declared fields

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; rv:122.0) Gecko/20100101 Firefox/122.0

Browser/OS: Firefox 122 on Mac OS X 10.15

View result in a separate tab

class without declared fields

18K/s

class with declared fields

5K/s

View exact numbers

Test name	Executions per second
✓ class without declared fields	17,663 Ops/sec
class with declared fields	5,372 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 benchmark and explain what's being tested, compared, and other considerations.

**Benchmark Definition JSON:**

The benchmark definition is a simple JavaScript class with two constructors: one with declared fields (`this.foo`, `this.bar`, `this.baz`) and another without declared fields. The classes have a single method `sum()` that returns the sum of their fields. Two test cases are defined:

1. **Class Without Declared Fields**: This test case creates an instance of the class using the constructor, and then uses a while loop to perform 1000 iterations. In each iteration, it calls the `foo`, `bar`, and `baz` properties directly, and also calls the `sum()` method.
2. **Class With Declared Fields**: Similar to the previous test case, but this time the class has declared fields (`this.foo`, `this.bar`, `this.baz`) that are accessible through the constructor.

**Comparison:**

The two test cases compare the performance of accessing properties directly versus using a getter method (in this case, the `sum()` method). The expected outcome is likely to be:

* **Class Without Declared Fields**: Faster execution time since direct property access is generally faster than calling a getter method.
* **Class With Declared Fields**: Slower execution time due to the additional overhead of calling the `sum()` method and accessing properties through it.

**Pros and Cons:**

* Direct Property Access:
	+ Pros: Faster, more efficient, and often used in native code or performance-critical sections.
	+ Cons: May require explicit property declarations (e.g., `private`, `protected`) to ensure private access.
* Getter Method (`sum()`):
	+ Pros: Easier to implement and maintain, provides a clear interface for accessing related data.
	+ Cons: Slower due to the additional overhead of method calls.

**Other Considerations:**

* **Library Usage**: The benchmark does not explicitly use any libraries or frameworks. However, it's worth noting that some browsers (like Firefox) may utilize their own internal optimizations and caching mechanisms when executing JavaScript code.
* **Special JS Features/Syntax**: There are no special features or syntax used in the benchmark definition.

**Alternatives:**

If you wanted to create a similar benchmark with different scenarios, here are some ideas:

1. Compare accessing properties using `this` versus direct property access (`obj.foo`) vs. using getters.
2. Benchmark iterating over an array versus using `forEach()` or other iteration methods.
3. Compare performance of object literals (e.g., `{ foo: 'bar', baz: 123 }`) versus class definitions.
4. Experiment with different browsers, device platforms, or operating systems to see how they affect execution times.

Feel free to modify the benchmark definition and explore different scenarios!

class with/without declared fields (version: 0) Benchmark.js

Comparing performance of: `class without declared fields vs class with declared fields`

Created: 2 years ago by: Guest

Go to the latest result

class without declared fields

class with declared fields

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

class with/without declared fields (version: 0) Benchmark.js

Comparing performance of: class without declared fields vs class with declared fields

Created: 2 years ago by: Guest

Go to the latest result

class without declared fields

class with declared fields

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Related benchmarks

Comparing performance of: `class without declared fields vs class with declared fields`