Interface IObservable<T>

interface IObservable<T = any> {
    changed: (callback: (newValue: T) => void) => IObservable<T>;
    computed: <K>(transform: (val: T) => K) => IObservable<K>;
    destroy: () => void;
    dispatch: (newValue: T) => IObservable<T>;
    equalTo: <K>(val: IObservableOr<K>) => IObservable<boolean>;
    grab: <K extends string | number | symbol>(
        key: K,
        defaultVal?: T[K],
    ) => IObservable;
    greaterThan: (val: IObservableOr<number>) => IObservable<boolean>;
    greaterThanOr: (val: IObservableOr<number>) => IObservable<boolean>;
    isEmpty: () => IObservable<boolean>;
    lessThan: (val: IObservableOr<number>) => IObservable<boolean>;
    lessThanOr: (val: IObservableOr<number>) => IObservable<boolean>;
    notEmpty: () => IObservable<boolean>;
    notEqualTo: <K>(val: IObservableOr<K>) => IObservable<boolean>;
    prev?: T;
    remove: (callback: (newValue: T) => void) => IObservable<T>;
    value: T;
}