Utility type to select only properties/methods/decorators

[TheColorRed]

Suggestion

🔍 Search Terms

• Utility Pick by Type
• Utility Pick by Decorator

✅ Viability Checklist

My suggestion meets these guidelines:

• This wouldn't be a breaking change in existing TypeScript/JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, new syntax sugar for JS, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.

⭐ Suggestion

Have additional Utility types that acts similar to Pick but allows to pick methods, properties, decorators.

📃 Motivating Example

This allows for a simpler way to get only properties, methods or specific items by decorator to create a new type.

export class MyClass {
  a: string;
  private b: number;
  @Input() color: string = 'red';

  c(){}
  protected d(){}
}

export type MyProperties = PickProperties<MyClass>;           // { a: string; b: number; color: string; }
export type MyProperties = PickProperties<MyClass, 'public'>; // { a: string; color: string; }

export type MyMethods = PickMethods<MyClass>;                 // { c: Function, d: Function; }
export type MyMethods = PickMethods<MyClass, 'protected'>;    // { d: Function; }

export type MyDecorators = PickDecorators<MyClass, 'Input'>;  // { color: string; }

💻 Use Cases

This would be helpful for picking properties/methods in classes with lots of items so that you wouldn't have to specifically define all the items to Omit or Pick individually.

[RyanCavanaugh]

We don't add new utility types that aren't required for declaration emit.

[typescript-bot]

This issue has been marked as "Declined" and has seen no recent activity. It has been automatically closed for house-keeping purposes.