@rbxts/reflector

Metadata Reflection API for Roblox-TS

The Reflector Class provides reflection capabilities, allowing you to introspect and
dynamically manipulate objects and classes. It offers methods to inspect and interact witha
properties, methods, and metadata of objects.

Installation

foo@bar:~$ pnpm add @rbxts/reflector
foo@bar:~$ npm install @rbxts/reflector
foo@bar:~$ yarn add @rbxts/reflector

Usage

import Reflector from "@rbxts/reflector"

// Define metadata for a class method declaratively.
class MyClass {
	@Reflector.defineMetadata(MyClass, "version", "1.0")
	myMethod() {...}

	anotherMethod() {...}
}

// Define metadata for a class method imperatively
Reflector.defineMetadata(MyClass, "description", "This is a method.", "anotherMethod");

// Retrieve metadata from a class.
const versionMetadata = Reflector.getMetadata(MyClass, "version");
// ^ versionMetadata: '1.0'

// Check if a class has specific metadata.
const hasVersionMetadata = Reflector.hasMetadata(MyClass, "version");
// ^ hasVersionMetadata: true

// Retrieve metadata keys for a class
const metadataKeys = Reflector.getMetadataKeys(MyClass);
// ^ metadataKeys: ['version']

// Using a decorator to add metadata to a class method.
function MyDecorator(value: string) {
	return function(target: any, propertyKey: PropertyKey, descriptor: TypedPropertyDescriptor<any>) {
		Reflector.defineMetadata(target, "something", value, propertyKey);
	}
}

class AnotherClass {
	@MyDecorator("Woah this is a method.")
	myMethod() {...}
}

const somethingMetadata = Reflector.getMetadata(AnotherClass, "something", "myMethod")
// ^ somethingMetadata: "Woah this is a method."

API

Reflector.defineMetadata(target, key, value, propertyKey?) (Overload 1)

Reflector.defineMetadata(key, value) (Overload 2)

Defines metadata for the specified object or class with the given key, value, and propertykey, or just the key and value if used in the declarative way.

• target (any) The object or class to define metadata for.
  
• key (string|symbol) The key identifying the metadata.
  
• value (any) The value of the metadata to set.
  
• propertyKey (string?)

Reflector.getMetadataKeys(target, propertyKey?)

Retrieves an array of keys for the metadata associated with the specific object or class.

• target (any) The object or class to define metadata for.
  
• propertyKey (string?)

Reflector.hasMetadata(target, propertyKey?)

Checks if the specified object or class has metadata associated with the given key.

• target (any) The object or class to define metadata for.
  
• key (string|symbol) The key identifying the metadata.
  
• propertyKey (string?)

Reflector.hasMetadata(target, propertyKey?)

Retrieves the metadata value associated with the given key on the specified object or class.

• target (any) The object or class to define metadata for.
  
• key (string|symbol) The key identifying the metadata.
  
• propertyKey (string?)

License

This project is licensed under the MIT License. See the LICENSE file for details.