Performance of Property Getters and Setters

To improve the performance of property getters and setters in your component, you can adopt an alternative change detection strategy. Using JavaScript Proxies, as mentioned previously, is a highly efficient way to observe property changes. Proxies allow you to intercept and customize operations performed on objects, such as getting, setting, and enumerating properties, without the overhead of manually defining getters and setters for each property.

Here's how you can implement a Proxy-based solution to replace the individual getters and setters:

Define a Proxy for Your Data Object: Create a Proxy to wrap your data object. This Proxy will intercept all get and set operations on the object.
Handle Changes in the Set Trap: In the set trap of the Proxy, you can implement the logic to detect changes to properties and take appropriate actions, like re-rendering the component or emitting events.
Integrate the Proxy with Your Component: Replace the manual getters and setters with the Proxy, and use it to handle all property interactions.

Here's an example implementation:

export function Component(options: any): any {
  return function <T extends ComponentClass>(OriginalClass: T) {
    return class extends HTMLElement {
      // ... existing code ...

      private _data: any = {};
      private _dataProxy;

      constructor(...args: any) {
        super();
        // ... existing constructor code ...

        // Initialize the proxy for data object
        this._dataProxy = new Proxy(this._data, {
          get: (target, property) => {
            // Optional: Add any additional logic for 'get' if needed
            return target[property];
          },
          set: (target, property, value) => {
            const oldValue = target[property];
            target[property] = value;
            this.onPropertyChanged(property, oldValue, value);
            return true; // Indicate success
          }
          // Optionally, you can add other traps like deleteProperty, etc.
        });

        this._data = this._dataProxy;
      }

      private onPropertyChanged(property, oldValue, newValue) {
        // Handle property changes
        if (oldValue !== newValue) {
          // Do something when the property changes
          // e.g., re-render the component or emit a custom event
          this.updateComponent();
        }
      }

      private updateComponent() {
        // Logic to update the component, if necessary
      }

      // ... rest of your code ...
    } as unknown as T;
  };
}

The _dataProxy is a Proxy that wraps the _data object.
The set trap handles changes to properties. When a property is set, it checks if the new value is different from the old one and calls onPropertyChanged.
The onPropertyChanged method contains the logic to handle property changes, such as updating the component.
This approach removes the need for individual getters and setters, thereby improving performance.

By using a Proxy, you centralize and simplify change detection, which can lead to better performance compared to manually defining getters and setters for each property. This method is also more scalable and maintainable, especially for components with a large number of properties.

MariaJunqueira / paw-core

Performance of Property Getters and Setters #23