<S, In, E = never, R = never>(
s: LazyArg<S>,
contFn: Predicate<S>,
f: (s: S, input: In) => Effect.Effect<S, E, R>
): Sink<S, In, In, E, R>A sink that folds its inputs with the provided function, termination predicate and initial state.
When to use
Use to accumulate stream input element by element with an effectful step and stop based on the accumulated state.
Details
The initial state is evaluated lazily. Each input element is folded with the
effectful function, and the sink continues while contFn returns true. If
the sink stops in the middle of a pulled array, the remaining elements from
that array are returned as leftovers.
Source effect/Sink.ts:72323 lines
export const const fold: <S, In, E = never, R = never>(
s: LazyArg<S>,
contFn: Predicate<S>,
f: (s: S, input: In) => Effect.Effect<S, E, R>
) => Sink<S, In, In, E, R>
A sink that folds its inputs with the provided function, termination
predicate and initial state.
When to use
Use to accumulate stream input element by element with an effectful step and
stop based on the accumulated state.
Details
The initial state is evaluated lazily. Each input element is folded with the
effectful function, and the sink continues while contFn returns true. If
the sink stops in the middle of a pulled array, the remaining elements from
that array are returned as leftovers.
fold = <function (type parameter) S in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>S, function (type parameter) In in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>In, function (type parameter) E in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>E = never, function (type parameter) R in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>R = never>(
s: LazyArg<S>s: type LazyArg<A> = () => AA zero-argument function that produces a value when invoked.
When to use
Use to type a lazy value provider that should not run until called.
Example (Creating a lazy argument)
import { Function } from "effect"
const constNull: Function.LazyArg<null> = Function.constant(null)
LazyArg<function (type parameter) S in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>S>,
contFn: Predicate<S>contFn: interface Predicate<in A>A function that decides whether a value of type A satisfies a condition.
When to use
Use when you want a reusable boolean check for A, especially when you plan
to combine checks with
and
/
or
or pass a predicate to arrays
and iterables.
Details
A predicate returns true or false and never throws by itself. It does not
narrow types unless you use Refinement.
Example (Defining a predicate)
import { Predicate } from "effect"
const isPositive: Predicate.Predicate<number> = (n) => n > 0
console.log(isPositive(1))
Type-level utilities for working with
Predicate
types.
When to use
Use when you need to extract input types from predicate signatures while
writing generic helpers over predicate types.
Details
These utilities are type-only, create no runtime values, and the namespace is
erased at runtime.
Example (Extracting predicate input)
import { Predicate } from "effect"
type IsString = Predicate.Predicate<string>
type Input = Predicate.Predicate.In<IsString>
Predicate<function (type parameter) S in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>S>,
f: (
s: S,
input: In
) => Effect.Effect<S, E, R>
s: Ss: function (type parameter) S in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>S, input: Ininput: function (type parameter) In in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>In) => import EffectEffect.interface Effect<out A, out E = never, out R = never>The Effect interface defines a value that lazily describes a workflow or
job. The workflow requires some context R, and may fail with an error of
type E, or succeed with a value of type A.
When to use
Use when you need to represent a lazy, composable workflow that can require
services, fail with a typed error, or succeed with a typed value.
Details
Effect values model resourceful interaction with the outside world,
including synchronous, asynchronous, concurrent, and parallel interaction.
They use a fiber-based concurrency model, with built-in support for
scheduling, fine-grained interruption, structured concurrency, and high
scalability.
To run an Effect value, you need a Runtime, which is a type that is
capable of executing Effect values.
Effect<function (type parameter) S in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>S, function (type parameter) E in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>E, function (type parameter) R in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>R>
): interface Sink<out A, in In = unknown, out L = never, out E = never, out R = never>A Sink<A, In, L, E, R> is used to consume elements produced by a Stream.
You can think of a sink as a function that will consume a variable amount of
In elements (could be 0, 1, or many), might fail with an error of type E,
and will eventually yield a value of type A together with a remainder of
type L (i.e. any leftovers).
Example (Running a sink with a stream)
import { Effect, Sink, Stream } from "effect"
// Create a simple sink that always succeeds with a value
const sink: Sink.Sink<number> = Sink.succeed(42)
// Use the sink to consume a stream
const stream = Stream.make(1, 2, 3)
const program = Stream.run(stream, sink)
Effect.runPromise(program).then(console.log)
// Output: 42
Namespace containing types and interfaces for Sink variance and type relationships.
Sink<function (type parameter) S in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>S, function (type parameter) In in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>In, function (type parameter) In in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>In, function (type parameter) E in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>E, function (type parameter) R in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>R> =>
const fromTransform: <
In,
A,
E,
R,
L = never
>(
transform: (
upstream: Pull.Pull<
NonEmptyReadonlyArray<In>,
never,
void
>,
scope: Scope.Scope
) => Effect.Effect<End<A, L>, E, R>
) => Sink<A, In, L, E, R>
Creates a Sink from a low-level transform function.
Details
The transform receives the upstream pull of non-empty input arrays and the
active scope, and returns an effect that completes with the sink's End
value.
fromTransform((upstream: Pull.Pull<
readonly [In, ...In[]],
never,
void,
never
>
(parameter) upstream: {
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
let state: Sstate = s: LazyArg<S>s()
return import EffectEffect.const gen: {
<Eff extends Effect<any, any, any>, AEff>(
f: () => Generator<Eff, AEff, never>
): Effect<
AEff,
[Eff] extends [never]
? never
: [Eff] extends [
Effect<infer _A, infer E, infer _R>
]
? E
: never,
[Eff] extends [never]
? never
: [Eff] extends [
Effect<infer _A, infer _E, infer R>
]
? R
: never
>
<Self, Eff extends Effect<any, any, any>, AEff>(
options: { readonly self: Self },
f: (this: Self) => Generator<Eff, AEff, never>
): Effect<
AEff,
[Eff] extends [never]
? never
: [Eff] extends [
Effect<infer _A, infer E, infer _R>
]
? E
: never,
[Eff] extends [never]
? never
: [Eff] extends [
Effect<infer _A, infer _E, infer R>
]
? R
: never
>
}
const arr: readonly [In, ...In[]]const arr: {
0: In;
length: number;
toString: () => string;
toLocaleString: { (): string; (locales: string | string[], options?: Intl.NumberFormatOptions & Intl.DateTimeFormatOptions): string };
concat: { (...items: Array<ConcatArray<In>>): Array<In>; (...items: Array<In | ConcatArray<In>>): Array<In> };
join: (separator?: string) => string;
slice: (start?: number, end?: number) => Array<In>;
indexOf: (searchElement: In, fromIndex?: number) => number;
lastIndexOf: (searchElement: In, fromIndex?: number) => number;
every: { (predicate: (value: In, index: number, array: ReadonlyArray<In>) => value is S, thisArg?: any): this is readonly S[]; (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any): boolean };
some: (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any) => boolean;
forEach: (callbackfn: (value: In, index: number, array: ReadonlyArray<In>) => void, thisArg?: any) => void;
map: (callbackfn: (value: In, index: number, array: ReadonlyArray<In>) => U, thisArg?: any) => Array<U>;
filter: { (predicate: (value: In, index: number, array: ReadonlyArray<In>) => value is S, thisArg?: any): Array<S>; (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any): Array<In> };
reduce: { (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In): In; (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In, initialValue: In): I…;
reduceRight: { (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In): In; (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In, initialValue: In): I…;
find: { (predicate: (value: In, index: number, obj: ReadonlyArray<In>) => value is S, thisArg?: any): S | undefined; (predicate: (value: In, index: number, obj: ReadonlyArray<In>) => unknown, thisArg?: any): In | undefined };
findIndex: (predicate: (value: In, index: number, obj: ReadonlyArray<In>) => unknown, thisArg?: any) => number;
entries: () => ArrayIterator<[number, In]>;
keys: () => ArrayIterator<number>;
values: () => ArrayIterator<In>;
includes: (searchElement: In, fromIndex?: number) => boolean;
flatMap: (callback: (this: This, value: In, index: number, array: Array<In>) => U | ReadonlyArray<U>, thisArg?: This | undefined) => Array<U>;
flat: (this: A, depth?: D | undefined) => Array<FlatArray<A, D>>;
at: (index: number) => In | undefined;
findLast: { (predicate: (value: In, index: number, array: ReadonlyArray<In>) => value is S, thisArg?: any): S | undefined; (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any): In | undefined };
findLastIndex: (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any) => number;
toReversed: () => Array<In>;
toSorted: (compareFn?: ((a: In, b: In) => number) | undefined) => Array<In>;
toSpliced: { (start: number, deleteCount: number, ...items: Array<In>): Array<In>; (start: number, deleteCount?: number): Array<In> };
with: (index: number, value: In) => Array<In>;
}
upstream: Pull.Pull<
readonly [In, ...In[]],
never,
void,
never
>
(parameter) upstream: {
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
let i: numberi = 0; let i: numberi < const arr: readonly [In, ...In[]]const arr: {
0: In;
length: number;
toString: () => string;
toLocaleString: { (): string; (locales: string | string[], options?: Intl.NumberFormatOptions & Intl.DateTimeFormatOptions): string };
concat: { (...items: Array<ConcatArray<In>>): Array<In>; (...items: Array<In | ConcatArray<In>>): Array<In> };
join: (separator?: string) => string;
slice: (start?: number, end?: number) => Array<In>;
indexOf: (searchElement: In, fromIndex?: number) => number;
lastIndexOf: (searchElement: In, fromIndex?: number) => number;
every: { (predicate: (value: In, index: number, array: ReadonlyArray<In>) => value is S, thisArg?: any): this is readonly S[]; (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any): boolean };
some: (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any) => boolean;
forEach: (callbackfn: (value: In, index: number, array: ReadonlyArray<In>) => void, thisArg?: any) => void;
map: (callbackfn: (value: In, index: number, array: ReadonlyArray<In>) => U, thisArg?: any) => Array<U>;
filter: { (predicate: (value: In, index: number, array: ReadonlyArray<In>) => value is S, thisArg?: any): Array<S>; (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any): Array<In> };
reduce: { (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In): In; (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In, initialValue: In): I…;
reduceRight: { (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In): In; (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In, initialValue: In): I…;
find: { (predicate: (value: In, index: number, obj: ReadonlyArray<In>) => value is S, thisArg?: any): S | undefined; (predicate: (value: In, index: number, obj: ReadonlyArray<In>) => unknown, thisArg?: any): In | undefined };
findIndex: (predicate: (value: In, index: number, obj: ReadonlyArray<In>) => unknown, thisArg?: any) => number;
entries: () => ArrayIterator<[number, In]>;
keys: () => ArrayIterator<number>;
values: () => ArrayIterator<In>;
includes: (searchElement: In, fromIndex?: number) => boolean;
flatMap: (callback: (this: This, value: In, index: number, array: Array<In>) => U | ReadonlyArray<U>, thisArg?: This | undefined) => Array<U>;
flat: (this: A, depth?: D | undefined) => Array<FlatArray<A, D>>;
at: (index: number) => In | undefined;
findLast: { (predicate: (value: In, index: number, array: ReadonlyArray<In>) => value is S, thisArg?: any): S | undefined; (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any): In | undefined };
findLastIndex: (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any) => number;
toReversed: () => Array<In>;
toSorted: (compareFn?: ((a: In, b: In) => number) | undefined) => Array<In>;
toSpliced: { (start: number, deleteCount: number, ...items: Array<In>): Array<In>; (start: number, deleteCount?: number): Array<In> };
with: (index: number, value: In) => Array<In>;
}
length: numberlength; let i: numberi++) {
let state: Sstate = yield* f: (
s: S,
input: In
) => Effect.Effect<S, E, R>
let state: Sstate, const arr: readonly [In, ...In[]]const arr: {
0: In;
length: number;
toString: () => string;
toLocaleString: { (): string; (locales: string | string[], options?: Intl.NumberFormatOptions & Intl.DateTimeFormatOptions): string };
concat: { (...items: Array<ConcatArray<In>>): Array<In>; (...items: Array<In | ConcatArray<In>>): Array<In> };
join: (separator?: string) => string;
slice: (start?: number, end?: number) => Array<In>;
indexOf: (searchElement: In, fromIndex?: number) => number;
lastIndexOf: (searchElement: In, fromIndex?: number) => number;
every: { (predicate: (value: In, index: number, array: ReadonlyArray<In>) => value is S, thisArg?: any): this is readonly S[]; (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any): boolean };
some: (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any) => boolean;
forEach: (callbackfn: (value: In, index: number, array: ReadonlyArray<In>) => void, thisArg?: any) => void;
map: (callbackfn: (value: In, index: number, array: ReadonlyArray<In>) => U, thisArg?: any) => Array<U>;
filter: { (predicate: (value: In, index: number, array: ReadonlyArray<In>) => value is S, thisArg?: any): Array<S>; (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any): Array<In> };
reduce: { (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In): In; (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In, initialValue: In): I…;
reduceRight: { (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In): In; (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In, initialValue: In): I…;
find: { (predicate: (value: In, index: number, obj: ReadonlyArray<In>) => value is S, thisArg?: any): S | undefined; (predicate: (value: In, index: number, obj: ReadonlyArray<In>) => unknown, thisArg?: any): In | undefined };
findIndex: (predicate: (value: In, index: number, obj: ReadonlyArray<In>) => unknown, thisArg?: any) => number;
entries: () => ArrayIterator<[number, In]>;
keys: () => ArrayIterator<number>;
values: () => ArrayIterator<In>;
includes: (searchElement: In, fromIndex?: number) => boolean;
flatMap: (callback: (this: This, value: In, index: number, array: Array<In>) => U | ReadonlyArray<U>, thisArg?: This | undefined) => Array<U>;
flat: (this: A, depth?: D | undefined) => Array<FlatArray<A, D>>;
at: (index: number) => In | undefined;
findLast: { (predicate: (value: In, index: number, array: ReadonlyArray<In>) => value is S, thisArg?: any): S | undefined; (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any): In | undefined };
findLastIndex: (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any) => number;
toReversed: () => Array<In>;
toSorted: (compareFn?: ((a: In, b: In) => number) | undefined) => Array<In>;
toSpliced: { (start: number, deleteCount: number, ...items: Array<In>): Array<In>; (start: number, deleteCount?: number): Array<In> };
with: (index: number, value: In) => Array<In>;
}
let i: numberi])
if (contFn: Predicate<S>contFn(let state: Sstate)) continue
return [
let state: Sstate,
(let i: numberi + 1) < const arr: readonly [In, ...In[]]const arr: {
0: In;
length: number;
toString: () => string;
toLocaleString: { (): string; (locales: string | string[], options?: Intl.NumberFormatOptions & Intl.DateTimeFormatOptions): string };
concat: { (...items: Array<ConcatArray<In>>): Array<In>; (...items: Array<In | ConcatArray<In>>): Array<In> };
join: (separator?: string) => string;
slice: (start?: number, end?: number) => Array<In>;
indexOf: (searchElement: In, fromIndex?: number) => number;
lastIndexOf: (searchElement: In, fromIndex?: number) => number;
every: { (predicate: (value: In, index: number, array: ReadonlyArray<In>) => value is S, thisArg?: any): this is readonly S[]; (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any): boolean };
some: (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any) => boolean;
forEach: (callbackfn: (value: In, index: number, array: ReadonlyArray<In>) => void, thisArg?: any) => void;
map: (callbackfn: (value: In, index: number, array: ReadonlyArray<In>) => U, thisArg?: any) => Array<U>;
filter: { (predicate: (value: In, index: number, array: ReadonlyArray<In>) => value is S, thisArg?: any): Array<S>; (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any): Array<In> };
reduce: { (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In): In; (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In, initialValue: In): I…;
reduceRight: { (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In): In; (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In, initialValue: In): I…;
find: { (predicate: (value: In, index: number, obj: ReadonlyArray<In>) => value is S, thisArg?: any): S | undefined; (predicate: (value: In, index: number, obj: ReadonlyArray<In>) => unknown, thisArg?: any): In | undefined };
findIndex: (predicate: (value: In, index: number, obj: ReadonlyArray<In>) => unknown, thisArg?: any) => number;
entries: () => ArrayIterator<[number, In]>;
keys: () => ArrayIterator<number>;
values: () => ArrayIterator<In>;
includes: (searchElement: In, fromIndex?: number) => boolean;
flatMap: (callback: (this: This, value: In, index: number, array: Array<In>) => U | ReadonlyArray<U>, thisArg?: This | undefined) => Array<U>;
flat: (this: A, depth?: D | undefined) => Array<FlatArray<A, D>>;
at: (index: number) => In | undefined;
findLast: { (predicate: (value: In, index: number, array: ReadonlyArray<In>) => value is S, thisArg?: any): S | undefined; (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any): In | undefined };
findLastIndex: (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any) => number;
toReversed: () => Array<In>;
toSorted: (compareFn?: ((a: In, b: In) => number) | undefined) => Array<In>;
toSpliced: { (start: number, deleteCount: number, ...items: Array<In>): Array<In>; (start: number, deleteCount?: number): Array<In> };
with: (index: number, value: In) => Array<In>;
}
length: numberlength ? (const arr: readonly [In, ...In[]]const arr: {
0: In;
length: number;
toString: () => string;
toLocaleString: { (): string; (locales: string | string[], options?: Intl.NumberFormatOptions & Intl.DateTimeFormatOptions): string };
concat: { (...items: Array<ConcatArray<In>>): Array<In>; (...items: Array<In | ConcatArray<In>>): Array<In> };
join: (separator?: string) => string;
slice: (start?: number, end?: number) => Array<In>;
indexOf: (searchElement: In, fromIndex?: number) => number;
lastIndexOf: (searchElement: In, fromIndex?: number) => number;
every: { (predicate: (value: In, index: number, array: ReadonlyArray<In>) => value is S, thisArg?: any): this is readonly S[]; (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any): boolean };
some: (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any) => boolean;
forEach: (callbackfn: (value: In, index: number, array: ReadonlyArray<In>) => void, thisArg?: any) => void;
map: (callbackfn: (value: In, index: number, array: ReadonlyArray<In>) => U, thisArg?: any) => Array<U>;
filter: { (predicate: (value: In, index: number, array: ReadonlyArray<In>) => value is S, thisArg?: any): Array<S>; (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any): Array<In> };
reduce: { (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In): In; (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In, initialValue: In): I…;
reduceRight: { (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In): In; (callbackfn: (previousValue: In, currentValue: In, currentIndex: number, array: ReadonlyArray<In>) => In, initialValue: In): I…;
find: { (predicate: (value: In, index: number, obj: ReadonlyArray<In>) => value is S, thisArg?: any): S | undefined; (predicate: (value: In, index: number, obj: ReadonlyArray<In>) => unknown, thisArg?: any): In | undefined };
findIndex: (predicate: (value: In, index: number, obj: ReadonlyArray<In>) => unknown, thisArg?: any) => number;
entries: () => ArrayIterator<[number, In]>;
keys: () => ArrayIterator<number>;
values: () => ArrayIterator<In>;
includes: (searchElement: In, fromIndex?: number) => boolean;
flatMap: (callback: (this: This, value: In, index: number, array: Array<In>) => U | ReadonlyArray<U>, thisArg?: This | undefined) => Array<U>;
flat: (this: A, depth?: D | undefined) => Array<FlatArray<A, D>>;
at: (index: number) => In | undefined;
findLast: { (predicate: (value: In, index: number, array: ReadonlyArray<In>) => value is S, thisArg?: any): S | undefined; (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any): In | undefined };
findLastIndex: (predicate: (value: In, index: number, array: ReadonlyArray<In>) => unknown, thisArg?: any) => number;
toReversed: () => Array<In>;
toSorted: (compareFn?: ((a: In, b: In) => number) | undefined) => Array<In>;
toSpliced: { (start: number, deleteCount: number, ...items: Array<In>): Array<In>; (start: number, deleteCount?: number): Array<In> };
with: (index: number, value: In) => Array<In>;
}
ReadonlyArray<In>.slice(start?: number, end?: number): In[]Returns a section of an array.
slice(let i: numberi + 1) as any) : var undefinedundefined
] as type const = readonly [S, any]const
}
}
}).Pipeable.pipe<Effect.Effect<readonly [S, any], Cause.Done<void> | E, R>, Effect.Effect<readonly [S, any] | End<S, In>, Exclude<E, Cause.Done<any>>, R>>(this: Effect.Effect<readonly [S, any], Cause.Done<void> | E, R>, ab: (_: Effect.Effect<readonly [S, any], Cause.Done<void> | E, R>) => Effect.Effect<readonly [S, any] | End<S, In>, Exclude<E, Cause.Done<any>>, R>): Effect.Effect<readonly [S, any] | End<S, In>, Exclude<...>, R> (+21 overloads)pipe(
import PullPull.const catchDone: {
<E, A2, E2, R2>(
f: (
leftover: Cause.Done.Extract<E>
) => Effect<A2, E2, R2>
): <A, R>(
self: Effect<A, E, R>
) => Effect<A | A2, ExcludeDone<E> | E2, R | R2>
<A, R, E, A2, E2, R2>(
self: Effect<A, E, R>,
f: (
leftover: Cause.Done.Extract<E>
) => Effect<A2, E2, R2>
): Effect<A | A2, ExcludeDone<E> | E2, R | R2>
}
import EffectEffect.const succeed: <A>(value: A) => Effect<A>Creates an Effect that always succeeds with a given value.
When to use
Use when an effect should complete successfully with a specific value without any errors
or external dependencies.
Example (Creating a successful effect)
import { Effect } from "effect"
// Creating an effect that represents a successful scenario
//
// ┌─── Effect<number, never, never>
// ▼
const success = Effect.succeed(42)
succeed<type End<A, L = never> = readonly [
value: A,
leftover?: readonly [L, ...L[]] | undefined
]
Tuple returned when a Sink finishes.
Details
The first element is the sink result. The optional second element contains a
non-empty array of leftover input that was pulled but not consumed.
End<function (type parameter) S in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>S, function (type parameter) In in <S, In, E = never, R = never>(s: LazyArg<S>, contFn: Predicate<S>, f: (s: S, input: In) => Effect.Effect<S, E, R>): Sink<S, In, In, E, R>In>>([let state: Sstate]))
)
})Referenced by 3 symbols