extensions/typescript-language-features/src/utils/dependentRegistration.ts/Condition/constructor
class Condition:	constructor(
		private readonly getValue: () => boolean,
		onUpdate: (handler: () => void) => void,
	) {
		super();
		this._value = this.getValue();

		onUpdate(() => {
			const newValue = this.getValue();
			if (newValue !== this._value) {
				this._value = newValue;
				this._onDidChange.fire();
			}
		});
	}