Method createExtension

packages/core/src/document.ts:196–202

* Creates a new Extension, for the extension type of the given constructor. If the * extension is already enabled for this Document, the previous Extension reference is reused.

(ctor: new (doc: Document) => T)

	 * extension is already enabled for this Document, the previous Extension reference is reused.
	 */
	createExtension<T extends Extension>(ctor: new (doc: Document) => T): T {
		const extensionName = (ctor as unknown as { EXTENSION_NAME: 'string' }).EXTENSION_NAME;
		const prevExtension = this.getRoot()
			.listExtensionsUsed()
			.find((ext) => ext.extensionName === extensionName);
		return (prevExtension || new ctor(this)) as T;
	}

	/**
	 * Disables and removes an {@link Extension} from the Document. If no Extension exists with