<K, A, E>(self: FiberMap<K, A, E>): Effect.Effect<number>Gets the number of fibers currently in the FiberMap.
Example (Checking the map size)
import { Effect, FiberMap } from "effect"
const program = Effect.gen(function*() {
const map = yield* FiberMap.make<string>()
console.log(yield* FiberMap.size(map)) // 0
// Add some fibers
yield* FiberMap.run(map, "task1", Effect.never)
yield* FiberMap.run(map, "task2", Effect.never)
console.log(yield* FiberMap.size(map)) // 2
})export const const size: <K, A, E>(
self: FiberMap<K, A, E>
) => Effect.Effect<number>
Gets the number of fibers currently in the FiberMap.
Example (Checking the map size)
import { Effect, FiberMap } from "effect"
const program = Effect.gen(function*() {
const map = yield* FiberMap.make<string>()
console.log(yield* FiberMap.size(map)) // 0
// Add some fibers
yield* FiberMap.run(map, "task1", Effect.never)
yield* FiberMap.run(map, "task2", Effect.never)
console.log(yield* FiberMap.size(map)) // 2
})
size = <function (type parameter) K in <K, A, E>(self: FiberMap<K, A, E>): Effect.Effect<number>K, function (type parameter) A in <K, A, E>(self: FiberMap<K, A, E>): Effect.Effect<number>A, function (type parameter) E in <K, A, E>(self: FiberMap<K, A, E>): Effect.Effect<number>E>(self: FiberMap<K, A, E>(parameter) self: {
deferred: Deferred.Deferred<void, unknown>;
state: { readonly _tag: "Open"; readonly backing: MutableHashMap.MutableHashMap<K, Fiber.Fiber<A, E>> } | { readonly _tag: "Closed" };
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;
}
interface FiberMap<in out K, out A = unknown, out E = unknown>A FiberMap is a collection of fibers, indexed by a key. When the associated
Scope is closed, all fibers in the map will be interrupted. Fibers are
automatically removed from the map when they complete.
Example (Managing fibers in a map)
import { Effect, FiberMap } from "effect"
// Create a FiberMap with string keys
const program = Effect.gen(function*() {
const map = yield* FiberMap.make<string>()
// Add some fibers to the map
yield* FiberMap.run(map, "task1", Effect.never)
yield* FiberMap.run(map, "task2", Effect.never)
// Get the size of the map
const size = yield* FiberMap.size(map)
console.log(size) // 2
})
FiberMap<function (type parameter) K in <K, A, E>(self: FiberMap<K, A, E>): Effect.Effect<number>K, function (type parameter) A in <K, A, E>(self: FiberMap<K, A, E>): Effect.Effect<number>A, function (type parameter) E in <K, A, E>(self: FiberMap<K, A, E>): Effect.Effect<number>E>): 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<number> =>
import EffectEffect.const sync: <A>(
thunk: LazyArg<A>
) => Effect<A>
Creates an Effect that represents a synchronous side-effectful computation.
When to use
Use when you need to wrap a synchronous side-effectful operation that is not
expected to throw.
Details
The provided function is evaluated lazily when the effect runs.
Gotchas
The function must not throw. If it throws, the thrown value is treated as a
defect, not as a typed failure. Use try when throwing is expected.
Example (Capturing synchronous logging in an Effect)
import { Effect } from "effect"
const log = (message: string) =>
Effect.sync(() => {
console.log(message) // side effect
})
// ┌─── Effect<void, never, never>
// ▼
const program = log("Hello, World!")
sync(() => self: FiberMap<K, A, E>(parameter) self: {
deferred: Deferred.Deferred<void, unknown>;
state: { readonly _tag: "Open"; readonly backing: MutableHashMap.MutableHashMap<K, Fiber.Fiber<A, E>> } | { readonly _tag: "Closed" };
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;
}
FiberMap<K, A, E>.state: { readonly _tag: "Open"; readonly backing: MutableHashMap.MutableHashMap<K, Fiber.Fiber<A, E>> } | { readonly _tag: "Closed" }state._tag: "Open" | "Closed"_tag === "Closed" ? 0 : import MutableHashMapMutableHashMap.const size: <K, V>(
self: MutableHashMap<K, V>
) => number
Returns the number of key-value pairs in the MutableHashMap.
When to use
Use to read how many entries are currently stored in the mutable hash map.
Example (Checking map size)
import { MutableHashMap } from "effect"
const map = MutableHashMap.empty<string, number>()
console.log(MutableHashMap.size(map)) // 0
MutableHashMap.set(map, "key1", 42)
MutableHashMap.set(map, "key2", 100)
console.log(MutableHashMap.size(map)) // 2
MutableHashMap.remove(map, "key1")
console.log(MutableHashMap.size(map)) // 1
MutableHashMap.clear(map)
console.log(MutableHashMap.size(map)) // 0
size(self: FiberMap<K, A, E>(parameter) self: {
deferred: Deferred.Deferred<void, unknown>;
state: { readonly _tag: "Open"; readonly backing: MutableHashMap.MutableHashMap<K, Fiber.Fiber<A, E>> } | { readonly _tag: "Closed" };
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;
}
FiberMap<K, A, E>.state: { readonly _tag: "Open"; readonly backing: MutableHashMap.MutableHashMap<K, Fiber.Fiber<A, E>> } | { readonly _tag: "Closed" }state.backing: MutableHashMap.MutableHashMap<
K,
Fiber.Fiber<A, E>
>
(property) backing: {
backing: Map<K, V>;
buckets: Map<number, NonEmptyArray<K>>;
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;
}