Benchmark: class vs fn - MeasureThat.net

HTML Preparation code:

<!--your preparation HTML code goes here-->

Script Preparation code:

// Класс с ленивой инициализацией
class StateClass {
  constructor() {
    this._state = null;
  }
  
  getState() {
    if (this._state === null) {
      // Имитация более дорогой операции
      const arr = Array.from({length: 1000}, (_, i) => i * Math.random());
      this._state = { 
        data: arr,
        computed: arr.reduce((a, b) => a + b, 0),
        timestamp: Date.now() 
      };
    }
    return this._state;
  }
}

// Замыкание с ленивой инициализацией
function createStateClosure() {
  let state = null;
  
  return function getState() {
    if (state === null) {
      // Имитация более дорогой операции
      const arr = Array.from({length: 1000}, (_, i) => i * Math.random());
      state = { 
        data: arr,
        computed: arr.reduce((a, b) => a + b, 0),
        timestamp: Date.now() 
      };
    }
    return state;
  };
}
let arrClass;
let arrFn;

Tests:

create arrClass
arrClass = Array.from({length: 1000}, (_, i) => new StateClass());
create arrFn
arrFn = Array.from({length: 1000}, (_, i) => createStateClosure());

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
create arrClass
create arrFn

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 10 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/137.0.0.0 Safari/537.36

Browser/OS: Chrome 137 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
create arrClass	49105.2 Ops/sec
create arrFn	46757.3 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated 10 months ago):

LLMs can make mistakes. Check important info.

The benchmark defined in the provided JSON is designed to compare the performance of two different approaches to lazy initialization in JavaScript: using a class (`StateClass`) versus a closure (`createStateClosure`). Let's break down the test and its components.

### Benchmarks Compared

1. **Implementation via Class (`StateClass`)**:
   - The `StateClass` is created with a constructor that initializes a private `_state` property to `null`. The `getState()` method checks if `_state` has been initialized:
     - If it hasn't, it simulates an expensive operation by generating an array of random numbers, computes its sum, and stores both in `_state`.
     - On subsequent calls, it returns the already initialized `_state`.

2. **Implementation via Closure (`createStateClosure`)**:
   - This method declares a variable `state` within the outer function scope and returns an inner function (`getState`) that behaves similarly to the class method.
   - The inner function checks if `state` is `null`, simulates the same expensive operation if true, and caches the result.

### Performance Analysis

- **Execution Results**:
   - `create arrClass`: Approximately 49,105 executions per second.
   - `create arrFn`: Approximately 46,757 executions per second.

### Pros and Cons

#### Class Implementation (`StateClass`)
**Pros**:
- **Encapsulation**: The use of a class offers a clearer structure, encapsulating the state and logic in an object-oriented style.
- **Future Extensions**: Easier to extend with inheritance and other object-oriented principles.

**Cons**:
- **Overhead**: Classes might introduce overhead due to object instantiation and prototype chain lookups.

#### Closure Implementation (`createStateClosure`)
**Pros**:
- **Simplicity**: A functional programming approach that avoids the overhead associated with classes.
- **Lightweight**: Since closures do not involve creating objects, they may perform faster under some conditions.

**Cons**:
- **Readability**: For developers unfamiliar with functional patterns, closures can be less intuitive than class-based structures.

### Other Considerations

- **Memory Usage**: Depending on the implementation and usage patterns, memory consumption may vary. Classes may maintain more metadata, whereas closures can sometimes be more efficient.
- **Compatibility and Use Cases**: Certain contexts (like React components) might favor one approach over the other based on state management needs.

### Similar Alternatives
1. **Factory Functions**: Similar to closures, but can be designed to return different objects for each call.
2. **Module Pattern**: Another method of encapsulating state and behavior using closures that can provide private and public methods.
3. **React Hooks**: For lazy state initialization in functional components (`useState`), leveraging React's built-in hooks may be an alternative approach for UI-focused applications.

### Conclusion
The benchmark effectively illustrates how two distinct paradigms in JavaScript can achieve similar goals—lazy initialization—with different performance implications. A direct comparison in terms of execution speed provides insights, but each approach has its own trade-offs that developers should consider based on application architecture, performance needs, and team familiarity with paradigms.

Related benchmarks:

class vs fn (version: 1)

Comparing performance of: create arrClass vs create arrFn

Created: 10 months ago by: Guest

Jump to the latest result

create arrClass

create arrFn

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated 10 months ago):