export declare const make: <A>(value: A) => Effect.Effect<Ref<A>, never, never>

export declare const get: <A>(self: Ref<A>) => Effect.Effect<A, never, never>

export interface Ref<in out A> extends Ref.Variance<A>, Readable<A> {
  modify<B>(f: (a: A) => readonly [B, A]): Effect.Effect<B>
}

export interface Variance<in out A> {
  readonly [RefTypeId]: {
    readonly _A: Types.Invariant<A>
  }
}

export declare const RefTypeId: typeof RefTypeId

export type RefTypeId = typeof RefTypeId

export declare const unsafeMake: <A>(value: A) => Ref<A>

export declare const getAndSet: {
  <A>(value: A): (self: Ref<A>) => Effect.Effect<A, never, never>
  <A>(self: Ref<A>, value: A): Effect.Effect<A, never, never>
}

export declare const getAndUpdate: {
  <A>(f: (a: A) => A): (self: Ref<A>) => Effect.Effect<A, never, never>
  <A>(self: Ref<A>, f: (a: A) => A): Effect.Effect<A, never, never>
}

export declare const getAndUpdateSome: {
  <A>(pf: (a: A) => Option.Option<A>): (self: Ref<A>) => Effect.Effect<A, never, never>
  <A>(self: Ref<A>, pf: (a: A) => Option.Option<A>): Effect.Effect<A, never, never>
}

export declare const modify: {
  <A, B>(f: (a: A) => readonly [B, A]): (self: Ref<A>) => Effect.Effect<B, never, never>
  <A, B>(self: Ref<A>, f: (a: A) => readonly [B, A]): Effect.Effect<B, never, never>
}

export declare const modifySome: {
  <B, A>(fallback: B, pf: (a: A) => Option.Option<readonly [B, A]>): (self: Ref<A>) => Effect.Effect<B, never, never>
  <A, B>(self: Ref<A>, fallback: B, pf: (a: A) => Option.Option<readonly [B, A]>): Effect.Effect<B, never, never>
}

export declare const set: {
  <A>(value: A): (self: Ref<A>) => Effect.Effect<void>
  <A>(self: Ref<A>, value: A): Effect.Effect<void>
}

export declare const setAndGet: {
  <A>(value: A): (self: Ref<A>) => Effect.Effect<A, never, never>
  <A>(self: Ref<A>, value: A): Effect.Effect<A, never, never>
}

export declare const update: {
  <A>(f: (a: A) => A): (self: Ref<A>) => Effect.Effect<void>
  <A>(self: Ref<A>, f: (a: A) => A): Effect.Effect<void>
}

export declare const updateAndGet: {
  <A>(f: (a: A) => A): (self: Ref<A>) => Effect.Effect<A, never, never>
  <A>(self: Ref<A>, f: (a: A) => A): Effect.Effect<A, never, never>
}

export declare const updateSome: {
  <A>(f: (a: A) => Option.Option<A>): (self: Ref<A>) => Effect.Effect<void>
  <A>(self: Ref<A>, f: (a: A) => Option.Option<A>): Effect.Effect<void>
}

export declare const updateSomeAndGet: {
  <A>(pf: (a: A) => Option.Option<A>): (self: Ref<A>) => Effect.Effect<A, never, never>
  <A>(self: Ref<A>, pf: (a: A) => Option.Option<A>): Effect.Effect<A, never, never>
}