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effect

TRef overview

Added in v2.0.0

Table of contents

constructors

make

Signature

export declare const make: <A>(value: A) => STM.STM<TRef<A>, never, never>

Added in v2.0.0

models

TRef (interface)

A TRef<A> is a purely functional description of a mutable reference that can be modified as part of a transactional effect. The fundamental operations of a TRef are set and get. set transactionally sets the reference to a new value. get gets the current value of the reference.

NOTE: While TRef<A> provides the transactional equivalent of a mutable reference, the value inside the TRef should be immutable.

Signature

export interface TRef<in out A> extends TRef.Variance<A> {
  /**
   * Note: the method is unbound, exposed only for potential extensions.
   */
  modify<B>(f: (a: A) => readonly [B, A]): STM.STM<B>
}

Added in v2.0.0

mutations

get

Signature

export declare const get: <A>(self: TRef<A>) => STM.STM<A, never, never>

Added in v2.0.0

getAndSet

Signature

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

Added in v2.0.0

getAndUpdate

Signature

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

Added in v2.0.0

getAndUpdateSome

Signature

export declare const getAndUpdateSome: {
  <A>(f: (a: A) => Option.Option<A>): (self: TRef<A>) => STM.STM<A, never, never>
  <A>(self: TRef<A>, f: (a: A) => Option.Option<A>): STM.STM<A, never, never>
}

Added in v2.0.0

modify

Signature

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

Added in v2.0.0

modifySome

Signature

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

Added in v2.0.0

set

Signature

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

Added in v2.0.0

setAndGet

Signature

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

Added in v2.0.0

update

Signature

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

Added in v2.0.0

updateAndGet

Signature

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

Added in v2.0.0

updateSome

Signature

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

Added in v2.0.0

updateSomeAndGet

Signature

export declare const updateSomeAndGet: {
  <A>(f: (a: A) => Option.Option<A>): (self: TRef<A>) => STM.STM<A, never, never>
  <A>(self: TRef<A>, f: (a: A) => Option.Option<A>): STM.STM<A, never, never>
}

Added in v2.0.0

symbols

TRefTypeId

Signature

export declare const TRefTypeId: typeof TRefTypeId

Added in v2.0.0

TRefTypeId (type alias)

Signature

export type TRefTypeId = typeof TRefTypeId

Added in v2.0.0

utils

TRef (namespace)

Added in v2.0.0

Variance (interface)

Signature

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

Added in v2.0.0