/**
 * Stores Effect services in typed maps.
 *
 * A `Context` holds service implementations under `Context.Service` or
 * `Context.Reference` keys, and its type records which keys are present.
 * Effects use contexts as their environment, so services can be provided once
 * instead of passed through every function call. This module includes helpers
 * for creating keys, building contexts, adding and reading services, merging
 * contexts, and selecting or removing services.
 *
 * @stability stable
 * @since 4.0.0
 */
import type { Effect, EffectIterator } from "./Effect.ts";
import * as Equal from "./Equal.ts";
import { type LazyArg } from "./Function.ts";
import type { Inspectable } from "./Inspectable.ts";
import * as Option from "./Option.ts";
import type { Pipeable } from "./Pipeable.ts";
import type * as Types from "./Types.ts";
/**
 * String literal type used as the runtime type identifier for `Context`
 * service keys.
 *
 * @stability stable
 * @category type IDs
 * @since 4.0.0
 */
export type ServiceTypeId = "~effect/Context/Service";
/**
 * Runtime type identifier attached to `Context` service keys and used by
 * `isKey` to recognize them.
 *
 * @stability stable
 * @category type IDs
 * @since 4.0.0
 */
export declare const ServiceTypeId: ServiceTypeId;
/**
 * Typed identifier for a service stored in a `Context`.
 *
 * **When to use**
 *
 * Use as the typed handle for storing, retrieving, and requiring a specific
 * service in a `Context`.
 *
 * **Details**
 *
 * `Identifier` tracks the requirement in Effect types, while `Shape` is the
 * service implementation retrieved by the key. A key is also an Effect value,
 * so yielding it inside `Effect.gen` retrieves the service from the current
 * fiber context.
 *
 * @see {@link Service} for creating required service keys
 * @see {@link Reference} for creating service keys with default values
 *
 * @stability stable
 * @category models
 * @since 4.0.0
 */
export interface Key<out Identifier, out Shape> extends Effect<Shape, never, Identifier> {
    readonly [ServiceTypeId]: ServiceTypeId;
    readonly Service: Shape;
    readonly Identifier: Identifier;
    readonly key: string;
}
/**
 * Context key with helper methods for working with a service.
 *
 * **Details**
 *
 * `context` creates a one-service `Context`, `use` and `useSync` retrieve the
 * service from the current Effect context before applying a function, and `of`
 * is a type-level helper for service values.
 *
 * **Example** (Defining a service key)
 *
 * ```ts import.meta.vitest
 * import { Context } from "effect"
 *
 * // Define an identifier for a database service
 * const Database = Context.Service<{ query: (sql: string) => string }>(
 *   "Database"
 * )
 *
 * // The key can be used to store and retrieve services
 * const context = Context.make(Database, { query: (sql) => `Result: ${sql}` })
 * Context.get(context, Database).query("SELECT 1") // => "Result: SELECT 1"
 * ```
 *
 * @stability stable
 * @category services
 * @since 4.0.0
 */
export interface Service<in out Identifier, in out Shape> extends Key<Identifier, Shape> {
    of(this: void, self: Shape): Shape;
    context(self: Shape): Context<Identifier>;
    use<A, E, R>(f: (service: Shape) => Effect<A, E, R>): Effect<A, E, R | Identifier>;
    useSync<A>(f: (service: Shape) => A): Effect<A, never, Identifier>;
}
/**
 * Class-style service key produced by `Context.Service<Self, Shape>()("Id")`.
 *
 * **When to use**
 *
 * Use when declaring a service as a class so the class value can serve as the
 * `Context` key.
 *
 * **Details**
 *
 * The class itself is the `Context` key, and its string `key` identifies the
 * service at runtime.
 *
 * @see {@link Service} for creating function-style keys or class-style service keys
 *
 * @stability stable
 * @category services
 * @since 4.0.0
 */
export interface ServiceClass<in out Self, in out Identifier extends string, in out Shape> extends Service<Self, Shape> {
    new (_: never): ServiceClass.Shape<Identifier, Shape>;
    readonly key: Identifier;
}
/**
 * Namespace containing helper types for class-style `Context.Service`
 * declarations.
 *
 * @stability stable
 * @since 4.0.0
 */
export declare namespace ServiceClass {
    /**
     * Runtime and type-level metadata carried by a class-style service key,
     * including its service type identifier, string key, and service shape.
     *
     * @category services
     * @since 4.0.0
     */
    interface Shape<Identifier extends string, Service> {
        readonly [ServiceTypeId]: typeof ServiceTypeId;
        readonly key: Identifier;
        readonly Service: Service;
    }
}
/**
 * Creates a `Context` service key.
 *
 * **When to use**
 *
 * Use when you need to define a context service key for a dependency that must
 * be provided by the surrounding context.
 *
 * **Details**
 *
 * Call `Context.Service("Key")` for a function-style key, or use the two-stage
 * form `Context.Service<Self, Shape>()("Key")` for class-style service
 * declarations. The returned key can be yielded as an Effect and passed to
 * `Context.make`, `Context.add`, and the Context getter functions.
 *
 * **Gotchas**
 *
 * The string key is the runtime identity of the service. Reusing the same key
 * string for unrelated services makes them occupy the same slot in a
 * `Context`.
 *
 * **Example** (Creating service keys)
 *
 * ```ts import.meta.vitest
 * import { Context } from "effect"
 *
 * // Create a simple service
 * const Database = Context.Service<{
 *   query: (sql: string) => string
 * }>("Database")
 *
 * // Create a service class
 * class Config extends Context.Service<Config, {
 *   port: number
 * }>()("Config") {}
 *
 * // Use the services to create contexts
 * const db = Context.make(Database, {
 *   query: (sql) => `Result: ${sql}`
 * })
 * const config = Context.make(Config, { port: 8080 })
 * Context.get(db, Database).query("SELECT 1") // => "Result: SELECT 1"
 * Context.get(config, Config).port // => 8080
 * ```
 *
 * @see {@link Reference} for service keys with default values
 *
 * @stability stable
 * @category services
 * @since 4.0.0
 */
export declare const Service: {
    /**
     * Creates a `Context` service key.
     *
     * **When to use**
     *
     * Use when you need to define a context service key for a dependency that must
     * be provided by the surrounding context.
     *
     * **Details**
     *
     * Call `Context.Service("Key")` for a function-style key, or use the two-stage
     * form `Context.Service<Self, Shape>()("Key")` for class-style service
     * declarations. The returned key can be yielded as an Effect and passed to
     * `Context.make`, `Context.add`, and the Context getter functions.
     *
     * **Gotchas**
     *
     * The string key is the runtime identity of the service. Reusing the same key
     * string for unrelated services makes them occupy the same slot in a
     * `Context`.
     *
     * **Example** (Creating service keys)
     *
     * ```ts import.meta.vitest
     * import { Context } from "effect"
     *
     * // Create a simple service
     * const Database = Context.Service<{
     *   query: (sql: string) => string
     * }>("Database")
     *
     * // Create a service class
     * class Config extends Context.Service<Config, {
     *   port: number
     * }>()("Config") {}
     *
     * // Use the services to create contexts
     * const db = Context.make(Database, {
     *   query: (sql) => `Result: ${sql}`
     * })
     * const config = Context.make(Config, { port: 8080 })
     * Context.get(db, Database).query("SELECT 1") // => "Result: SELECT 1"
     * Context.get(config, Config).port // => 8080
     * ```
     *
     * @see {@link Reference} for service keys with default values
     *
     * @stability stable
     * @category services
     * @since 4.0.0
     */
    <Identifier, Shape = Identifier>(key: string, options?: {} | undefined): Service<Identifier, Shape>;
    /**
     * Creates a `Context` service key.
     *
     * **When to use**
     *
     * Use when you need to define a context service key for a dependency that must
     * be provided by the surrounding context.
     *
     * **Details**
     *
     * Call `Context.Service("Key")` for a function-style key, or use the two-stage
     * form `Context.Service<Self, Shape>()("Key")` for class-style service
     * declarations. The returned key can be yielded as an Effect and passed to
     * `Context.make`, `Context.add`, and the Context getter functions.
     *
     * **Gotchas**
     *
     * The string key is the runtime identity of the service. Reusing the same key
     * string for unrelated services makes them occupy the same slot in a
     * `Context`.
     *
     * **Example** (Creating service keys)
     *
     * ```ts import.meta.vitest
     * import { Context } from "effect"
     *
     * // Create a simple service
     * const Database = Context.Service<{
     *   query: (sql: string) => string
     * }>("Database")
     *
     * // Create a service class
     * class Config extends Context.Service<Config, {
     *   port: number
     * }>()("Config") {}
     *
     * // Use the services to create contexts
     * const db = Context.make(Database, {
     *   query: (sql) => `Result: ${sql}`
     * })
     * const config = Context.make(Config, { port: 8080 })
     * Context.get(db, Database).query("SELECT 1") // => "Result: SELECT 1"
     * Context.get(config, Config).port // => 8080
     * ```
     *
     * @see {@link Reference} for service keys with default values
     *
     * @stability stable
     * @category services
     * @since 4.0.0
     */
    <Self, Shape>(): <const Identifier extends string, E, R = Types.unassigned, Args extends ReadonlyArray<any> = never>(id: Identifier, options?: {
        readonly make?: ((...args: Args) => Effect<Shape, E, R>) | Effect<Shape, E, R> | undefined;
    } | undefined) => ServiceClass<Self, Identifier, Shape> & ([Types.unassigned] extends [R] ? unknown : {
        readonly make: [Args] extends [never] ? Effect<Shape, E, R> : (...args: Args) => Effect<Shape, E, R>;
    });
    /**
     * Creates a `Context` service key.
     *
     * **When to use**
     *
     * Use when you need to define a context service key for a dependency that must
     * be provided by the surrounding context.
     *
     * **Details**
     *
     * Call `Context.Service("Key")` for a function-style key, or use the two-stage
     * form `Context.Service<Self, Shape>()("Key")` for class-style service
     * declarations. The returned key can be yielded as an Effect and passed to
     * `Context.make`, `Context.add`, and the Context getter functions.
     *
     * **Gotchas**
     *
     * The string key is the runtime identity of the service. Reusing the same key
     * string for unrelated services makes them occupy the same slot in a
     * `Context`.
     *
     * **Example** (Creating service keys)
     *
     * ```ts import.meta.vitest
     * import { Context } from "effect"
     *
     * // Create a simple service
     * const Database = Context.Service<{
     *   query: (sql: string) => string
     * }>("Database")
     *
     * // Create a service class
     * class Config extends Context.Service<Config, {
     *   port: number
     * }>()("Config") {}
     *
     * // Use the services to create contexts
     * const db = Context.make(Database, {
     *   query: (sql) => `Result: ${sql}`
     * })
     * const config = Context.make(Config, { port: 8080 })
     * Context.get(db, Database).query("SELECT 1") // => "Result: SELECT 1"
     * Context.get(config, Config).port // => 8080
     * ```
     *
     * @see {@link Reference} for service keys with default values
     *
     * @stability stable
     * @category services
     * @since 4.0.0
     */
    <Self>(): <const Identifier extends string, Make extends Effect<any, any, any> | ((...args: any) => Effect<any, any, any>)>(id: Identifier, options: {
        readonly make: Make;
    }) => ServiceClass<Self, Identifier, Make extends Effect<infer _A, infer _E, infer _R> | ((...args: infer _Args) => Effect<infer _A, infer _E, infer _R>) ? _A : never> & {
        readonly make: Make;
    };
};
declare const ReferenceTypeId: "~effect/Context/Reference";
/**
 * Service key with a lazily computed default value.
 *
 * **Details**
 *
 * When a `Reference` is requested from a `Context` that does not contain an
 * override, Context getters that resolve references return the cached default
 * value instead of failing.
 *
 * **Example** (Defining a reference with a default value)
 *
 * ```ts import.meta.vitest
 * import { Context } from "effect"
 *
 * // Define a reference with a default value
 * const messages: Array<string> = []
 * const LoggerRef: Context.Reference<{ log: (msg: string) => void }> =
 *   Context.Reference("Logger", {
 *     defaultValue: () => ({ log: (msg) => { messages.push(msg) } })
 *   })
 *
 * // The reference can be used without explicit provision
 * const context = Context.empty()
 * const logger = Context.get(context, LoggerRef) // Uses default value
 * logger.log("default logger")
 * messages // => ["default logger"]
 * ```
 *
 * @stability stable
 * @category services
 * @since 3.11.0
 */
export interface Reference<in out Shape> extends Service<never, Shape> {
    readonly [ReferenceTypeId]: typeof ReferenceTypeId;
    readonly defaultValue: () => Shape;
    [Symbol.iterator](): EffectIterator<Reference<Shape>>;
    new (_: never): {};
}
/**
 * Namespace containing utility types for `Context` service keys.
 *
 * **Example** (Extracting service types)
 *
 * ```ts import.meta.vitest
 * import { Context } from "effect"
 *
 * const Database = Context.Service<{
 *   query: (sql: string) => string
 * }>("Database")
 *
 * // Extract service type from a key
 * type DatabaseService = Context.Service.Shape<typeof Database>
 *
 * // Extract identifier type from a key
 * type DatabaseId = Context.Service.Identifier<typeof Database>
 *
 * Database.key // => "Database"
 * ```
 *
 * @stability stable
 * @since 2.0.0
 */
export declare namespace Service {
    /**
     * Type that matches any `Context` service key regardless of its identifier or
     * service shape.
     *
     * **Example** (Typing any service key)
     *
     * ```ts import.meta.vitest
     * import { Context } from "effect"
     *
     * // Any represents any possible service type
     * const services: Array<Context.Service.Any> = [
     *   Context.Service<{ log: (msg: string) => void }>("Logger"),
     *   Context.Service<{ query: (sql: string) => string }>("Database")
     * ]
     * services.map((service) => service.key) // => ["Logger", "Database"]
     * ```
     *
     * @category utility types
     * @since 4.0.0
     */
    type Any = Key<never, any> | Key<any, any>;
    /**
     * Extracts the service implementation type stored behind a `Context` service
     * key.
     *
     * **Example** (Extracting a service shape)
     *
     * ```ts import.meta.vitest
     * import { Context } from "effect"
     *
     * const Database = Context.Service<{ query: (sql: string) => string }>(
     *   "Database"
     * )
     *
     * // Extract the service shape from the service
     * type DatabaseService = Context.Service.Shape<typeof Database>
     * // DatabaseService is { query: (sql: string) => string }
     * Database.key // => "Database"
     * ```
     *
     * @category utility types
     * @since 4.0.0
     */
    type Shape<T> = T extends Key<infer _I, infer S> ? S : never;
    /**
     * Extracts the identifier, or requirement type, associated with a `Context`
     * service key.
     *
     * **Example** (Extracting a service identifier)
     *
     * ```ts import.meta.vitest
     * import { Context } from "effect"
     *
     * const Database = Context.Service<{ query: (sql: string) => string }>(
     *   "Database"
     * )
     *
     * // Extract the identifier type from a key
     * type DatabaseId = Context.Service.Identifier<typeof Database>
     * // DatabaseId is the identifier type
     * Database.key // => "Database"
     * ```
     *
     * @category utility types
     * @since 2.0.0
     */
    type Identifier<T> = T extends Key<infer I, infer _S> ? I : never;
}
declare const TypeId: "~effect/Context";
/**
 * Immutable collection of service implementations used for dependency
 * injection in Effect programs.
 *
 * **Details**
 *
 * The type parameter tracks the service identifiers available in the context.
 * At runtime, services are stored by each key's string `key`.
 *
 * **Example** (Creating a context with multiple services)
 *
 * ```ts import.meta.vitest
 * import { Context } from "effect"
 *
 * // Create a context with multiple services
 * const Logger = Context.Service<{ log: (msg: string) => void }>("Logger")
 * const Database = Context.Service<{ query: (sql: string) => string }>(
 *   "Database"
 * )
 *
 * const context = Context.make(Logger, { log: (_msg: string) => {} })
 *   .pipe(Context.add(Database, { query: (sql) => `Result: ${sql}` }))
 * Context.get(context, Database).query("SELECT 1") // => "Result: SELECT 1"
 * ```
 *
 * @stability stable
 * @category models
 * @since 2.0.0
 */
export interface Context<in Services> extends Equal.Equal, Pipeable, Inspectable {
    readonly [TypeId]: {
        readonly _Services: Types.Contravariant<Services>;
    };
    readonly mapUnsafe: ReadonlyMap<string, any>;
}
/**
 * Creates a `Context` from an existing service map.
 *
 * **When to use**
 *
 * Use when constructing a low-level `Context` from a trusted map whose lifecycle
 * you control.
 *
 * **Gotchas**
 *
 * The provided map is retained without copying and must not be mutated after
 * construction. Prefer `empty`, `make`, `add`, or `merge` for normal Context
 * construction.
 *
 * **Example** (Creating a context from a map)
 *
 * ```ts import.meta.vitest
 * import { Context } from "effect"
 *
 * // Create a context from a Map (unsafe)
 * const map = new Map([
 *   ["Logger", { log: (_msg: string) => {} }]
 * ])
 *
 * const context = Context.makeUnsafe(map)
 * context.mapUnsafe.size // => 1
 * ```
 *
 * @stability stable
 * @category constructors
 * @since 4.0.0
 */
export declare const makeUnsafe: <Services = never>(mapUnsafe: ReadonlyMap<string, any>) => Context<Services>;
/**
 * Checks whether the provided argument is a `Context`.
 *
 * **When to use**
 *
 * Use to narrow an unknown value before passing it to APIs that require a
 * `Context`.
 *
 * **Details**
 *
 * This checks the runtime `Context` marker and does not inspect which services
 * the context contains.
 *
 * **Gotchas**
 *
 * This guard only proves that the value is a `Context`; it does not prove that
 * any specific service is present.
 *
 * **Example** (Checking for contexts)
 *
 * ```ts import.meta.vitest
 * import { Context } from "effect"
 * Context.isContext(Context.empty()) // => true
 * ```
 *
 * @see {@link isKey} for checking service keys
 * @see {@link isReference} for checking references with defaults
 *
 * @stability stable
 * @category guards
 * @since 2.0.0
 */
export declare const isContext: (u: unknown) => u is Context<never>;
/**
 * Checks whether the provided argument is a `Key`.
 *
 * **Example** (Checking for keys)
 *
 * ```ts import.meta.vitest
 * import { Context } from "effect"
 * Context.isKey(Context.Service("Service")) // => true
 * ```
 *
 * @stability stable
 * @category guards
 * @since 4.0.0
 */
export declare const isKey: (u: unknown) => u is Key<any, any>;
/**
 * Checks whether the provided argument is a `Reference`.
 *
 * **Example** (Checking for references)
 *
 * ```ts import.meta.vitest
 * import { Context } from "effect"
 *
 * const LoggerRef = Context.Reference("Logger", {
 *   defaultValue: () => ({ log: (_msg: string) => {} })
 * })
 *
 * Context.isReference(LoggerRef) // => true
 * Context.isReference(Context.Service("Key")) // => false
 * ```
 *
 * @stability stable
 * @category guards
 * @since 3.11.0
 */
export declare const isReference: <I, S>(u: Key<I, S>) => u is Reference<S>;
/**
 * Returns an empty `Context`.
 *
 * **Example** (Creating an empty context)
 *
 * ```ts import.meta.vitest
 * import { Context } from "effect"
 * Context.empty().mapUnsafe.size // => 0
 * ```
 *
 * @stability stable
 * @category constructors
 * @since 2.0.0
 */
export declare const empty: () => Context<never>;
/**
 * Creates a new `Context` with a single service associated to the key.
 *
 * **Example** (Creating a context with one service)
 *
 * ```ts import.meta.vitest
 * import { Context } from "effect"
 *
 * const Port = Context.Service<{ PORT: number }>("Port")
 *
 * const context = Context.make(Port, { PORT: 8080 })
 *
 * Context.get(context, Port).PORT // => 8080
 * ```
 *
 * @stability stable
 * @category constructors
 * @since 2.0.0
 */
export declare const make: <I, S>(key: Key<I, S>, service: Types.NoInfer<S>) => Context<I>;
/**
 * Adds a service to a given `Context`.
 *
 * **When to use**
 *
 * Use when you need to store a known service value in a `Context`.
 *
 * **Details**
 *
 * If the context already contains the same service key, the new service
 * replaces the previous one.
 *
 * **Example** (Adding a service to a context)
 *
 * ```ts import.meta.vitest
 * import { Context, pipe } from "effect"
 *
 * const Port = Context.Service<{ PORT: number }>("Port")
 * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
 *
 * const someContext = Context.make(Port, { PORT: 8080 })
 *
 * const context = pipe(
 *   someContext,
 *   Context.add(Timeout, { TIMEOUT: 5000 })
 * )
 *
 * const values = [Context.get(context, Port).PORT, Context.get(context, Timeout).TIMEOUT]
 * values // => [8080, 5000]
 * ```
 *
 * @see {@link addOrOmit} for adding or removing a service from an `Option`
 *
 * @stability stable
 * @category combining
 * @since 2.0.0
 */
export declare const add: {
    /**
     * Adds a service to a given `Context`.
     *
     * **When to use**
     *
     * Use when you need to store a known service value in a `Context`.
     *
     * **Details**
     *
     * If the context already contains the same service key, the new service
     * replaces the previous one.
     *
     * **Example** (Adding a service to a context)
     *
     * ```ts import.meta.vitest
     * import { Context, pipe } from "effect"
     *
     * const Port = Context.Service<{ PORT: number }>("Port")
     * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
     *
     * const someContext = Context.make(Port, { PORT: 8080 })
     *
     * const context = pipe(
     *   someContext,
     *   Context.add(Timeout, { TIMEOUT: 5000 })
     * )
     *
     * const values = [Context.get(context, Port).PORT, Context.get(context, Timeout).TIMEOUT]
     * values // => [8080, 5000]
     * ```
     *
     * @see {@link addOrOmit} for adding or removing a service from an `Option`
     *
     * @stability stable
     * @category combining
     * @since 2.0.0
     */
    <I, S>(key: Key<I, S>, service: Types.NoInfer<S>): <Services>(self: Context<Services>) => Context<Services | I>;
    /**
     * Adds a service to a given `Context`.
     *
     * **When to use**
     *
     * Use when you need to store a known service value in a `Context`.
     *
     * **Details**
     *
     * If the context already contains the same service key, the new service
     * replaces the previous one.
     *
     * **Example** (Adding a service to a context)
     *
     * ```ts import.meta.vitest
     * import { Context, pipe } from "effect"
     *
     * const Port = Context.Service<{ PORT: number }>("Port")
     * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
     *
     * const someContext = Context.make(Port, { PORT: 8080 })
     *
     * const context = pipe(
     *   someContext,
     *   Context.add(Timeout, { TIMEOUT: 5000 })
     * )
     *
     * const values = [Context.get(context, Port).PORT, Context.get(context, Timeout).TIMEOUT]
     * values // => [8080, 5000]
     * ```
     *
     * @see {@link addOrOmit} for adding or removing a service from an `Option`
     *
     * @stability stable
     * @category combining
     * @since 2.0.0
     */
    <Services, I, S>(self: Context<Services>, key: Key<I, S>, service: Types.NoInfer<S>): Context<Services | I>;
};
/**
 * Adds a service by key to a given `Context` using a string key.
 *
 * @stability stable
 * @category combining
 * @since 4.0.0
 */
export declare const addUnsafe: <Services, I, S>(self: Context<Services>, key: string, service: Types.NoInfer<S>) => Context<Services | I>;
/**
 * Adds or removes a service depending on an `Option`.
 *
 * **When to use**
 *
 * Use when you need to add or omit a `Context` service based on an `Option`.
 *
 * **Details**
 *
 * When `service` is `Option.some`, the value is stored for the key. When it is
 * `Option.none`, the key is removed from the returned `Context`.
 *
 * **Example** (Adding optional services)
 *
 * ```ts import.meta.vitest
 * import { Context, Option } from "effect"
 *
 * const Port = Context.Service<{ PORT: number }>("Port")
 *
 * const withPort = Context.empty().pipe(
 *   Context.addOrOmit(Port, Option.some({ PORT: 8080 }))
 * )
 *
 * const withoutPort = withPort.pipe(
 *   Context.addOrOmit(Port, Option.none())
 * )
 * Context.getOption(withPort, Port) // => Option.some({ PORT: 8080 })
 * Context.getOption(withoutPort, Port) // => Option.none()
 * ```
 *
 * @see {@link add} for always storing a service value
 *
 * @stability stable
 * @category combining
 * @since 4.0.0
 */
export declare const addOrOmit: {
    /**
     * Adds or removes a service depending on an `Option`.
     *
     * **When to use**
     *
     * Use when you need to add or omit a `Context` service based on an `Option`.
     *
     * **Details**
     *
     * When `service` is `Option.some`, the value is stored for the key. When it is
     * `Option.none`, the key is removed from the returned `Context`.
     *
     * **Example** (Adding optional services)
     *
     * ```ts import.meta.vitest
     * import { Context, Option } from "effect"
     *
     * const Port = Context.Service<{ PORT: number }>("Port")
     *
     * const withPort = Context.empty().pipe(
     *   Context.addOrOmit(Port, Option.some({ PORT: 8080 }))
     * )
     *
     * const withoutPort = withPort.pipe(
     *   Context.addOrOmit(Port, Option.none())
     * )
     * Context.getOption(withPort, Port) // => Option.some({ PORT: 8080 })
     * Context.getOption(withoutPort, Port) // => Option.none()
     * ```
     *
     * @see {@link add} for always storing a service value
     *
     * @stability stable
     * @category combining
     * @since 4.0.0
     */
    <I, S>(key: Key<I, S>, service: Option.Option<Types.NoInfer<S>>): <Services>(self: Context<Services>) => Context<Exclude<Services, I>>;
    /**
     * Adds or removes a service depending on an `Option`.
     *
     * **When to use**
     *
     * Use when you need to add or omit a `Context` service based on an `Option`.
     *
     * **Details**
     *
     * When `service` is `Option.some`, the value is stored for the key. When it is
     * `Option.none`, the key is removed from the returned `Context`.
     *
     * **Example** (Adding optional services)
     *
     * ```ts import.meta.vitest
     * import { Context, Option } from "effect"
     *
     * const Port = Context.Service<{ PORT: number }>("Port")
     *
     * const withPort = Context.empty().pipe(
     *   Context.addOrOmit(Port, Option.some({ PORT: 8080 }))
     * )
     *
     * const withoutPort = withPort.pipe(
     *   Context.addOrOmit(Port, Option.none())
     * )
     * Context.getOption(withPort, Port) // => Option.some({ PORT: 8080 })
     * Context.getOption(withoutPort, Port) // => Option.none()
     * ```
     *
     * @see {@link add} for always storing a service value
     *
     * @stability stable
     * @category combining
     * @since 4.0.0
     */
    <Services, I, S>(self: Context<Services>, key: Key<I, S>, service: Option.Option<Types.NoInfer<S>>): Context<Exclude<Services, I>>;
};
/**
 * Gets the service for a key, or evaluates the fallback when a non-reference
 * key is absent.
 *
 * **When to use**
 *
 * Use when you need a fallback for a missing `Context.Service` key while still
 * resolving `Context.Reference` defaults.
 *
 * **Details**
 *
 * If the key is a `Context.Reference` and no override is stored in the
 * context, its cached default value is returned instead of the fallback.
 *
 * **Gotchas**
 *
 * The fallback is not evaluated for missing `Context.Reference` keys because
 * references resolve to their default value.
 *
 * **Example** (Falling back for missing services)
 *
 * ```ts import.meta.vitest
 * import { Context } from "effect"
 *
 * const Logger = Context.Service<{ log: (msg: string) => void }>("Logger")
 * const Database = Context.Service<{ query: (sql: string) => string }>(
 *   "Database"
 * )
 *
 * const context = Context.make(Logger, { log: (_msg: string) => {} })
 *
 * const logger = Context.getOrElse(context, Logger, () => ({ log: () => {} }))
 * const database = Context.getOrElse(
 *   context,
 *   Database,
 *   () => ({ query: () => "fallback" })
 * )
 *
 * logger === Context.get(context, Logger) // => true
 * database.query("SELECT 1") // => "fallback"
 * ```
 *
 * @see {@link getOption} for returning `Option.none` when a non-reference key is missing
 *
 * @stability stable
 * @category getters
 * @since 3.7.0
 */
export declare const getOrElse: {
    /**
     * Gets the service for a key, or evaluates the fallback when a non-reference
     * key is absent.
     *
     * **When to use**
     *
     * Use when you need a fallback for a missing `Context.Service` key while still
     * resolving `Context.Reference` defaults.
     *
     * **Details**
     *
     * If the key is a `Context.Reference` and no override is stored in the
     * context, its cached default value is returned instead of the fallback.
     *
     * **Gotchas**
     *
     * The fallback is not evaluated for missing `Context.Reference` keys because
     * references resolve to their default value.
     *
     * **Example** (Falling back for missing services)
     *
     * ```ts import.meta.vitest
     * import { Context } from "effect"
     *
     * const Logger = Context.Service<{ log: (msg: string) => void }>("Logger")
     * const Database = Context.Service<{ query: (sql: string) => string }>(
     *   "Database"
     * )
     *
     * const context = Context.make(Logger, { log: (_msg: string) => {} })
     *
     * const logger = Context.getOrElse(context, Logger, () => ({ log: () => {} }))
     * const database = Context.getOrElse(
     *   context,
     *   Database,
     *   () => ({ query: () => "fallback" })
     * )
     *
     * logger === Context.get(context, Logger) // => true
     * database.query("SELECT 1") // => "fallback"
     * ```
     *
     * @see {@link getOption} for returning `Option.none` when a non-reference key is missing
     *
     * @stability stable
     * @category getters
     * @since 3.7.0
     */
    <S, I, B>(key: Key<I, S>, orElse: LazyArg<B>): <Services>(self: Context<Services>) => S | B;
    /**
     * Gets the service for a key, or evaluates the fallback when a non-reference
     * key is absent.
     *
     * **When to use**
     *
     * Use when you need a fallback for a missing `Context.Service` key while still
     * resolving `Context.Reference` defaults.
     *
     * **Details**
     *
     * If the key is a `Context.Reference` and no override is stored in the
     * context, its cached default value is returned instead of the fallback.
     *
     * **Gotchas**
     *
     * The fallback is not evaluated for missing `Context.Reference` keys because
     * references resolve to their default value.
     *
     * **Example** (Falling back for missing services)
     *
     * ```ts import.meta.vitest
     * import { Context } from "effect"
     *
     * const Logger = Context.Service<{ log: (msg: string) => void }>("Logger")
     * const Database = Context.Service<{ query: (sql: string) => string }>(
     *   "Database"
     * )
     *
     * const context = Context.make(Logger, { log: (_msg: string) => {} })
     *
     * const logger = Context.getOrElse(context, Logger, () => ({ log: () => {} }))
     * const database = Context.getOrElse(
     *   context,
     *   Database,
     *   () => ({ query: () => "fallback" })
     * )
     *
     * logger === Context.get(context, Logger) // => true
     * database.query("SELECT 1") // => "fallback"
     * ```
     *
     * @see {@link getOption} for returning `Option.none` when a non-reference key is missing
     *
     * @stability stable
     * @category getters
     * @since 3.7.0
     */
    <Services, S, I, B>(self: Context<Services>, key: Key<I, S>, orElse: LazyArg<B>): S | B;
};
/**
 * Returns the service currently stored for a key, or `undefined` when the key
 * is absent.
 *
 * **When to use**
 *
 * Use when you need to read the service stored for a key without resolving
 * `Context.Reference` defaults.
 *
 * **Gotchas**
 *
 * This is a raw lookup and does not resolve default values for
 * `Context.Reference` keys.
 *
 * @see {@link getOption} for a reference-aware optional lookup
 *
 * @stability stable
 * @category getters
 * @since 4.0.0
 */
export declare const getOrUndefined: {
    /**
     * Returns the service currently stored for a key, or `undefined` when the key
     * is absent.
     *
     * **When to use**
     *
     * Use when you need to read the service stored for a key without resolving
     * `Context.Reference` defaults.
     *
     * **Gotchas**
     *
     * This is a raw lookup and does not resolve default values for
     * `Context.Reference` keys.
     *
     * @see {@link getOption} for a reference-aware optional lookup
     *
     * @stability stable
     * @category getters
     * @since 4.0.0
     */
    <S, I>(key: Key<I, S>): <Services>(self: Context<Services>) => S | undefined;
    /**
     * Returns the service currently stored for a key, or `undefined` when the key
     * is absent.
     *
     * **When to use**
     *
     * Use when you need to read the service stored for a key without resolving
     * `Context.Reference` defaults.
     *
     * **Gotchas**
     *
     * This is a raw lookup and does not resolve default values for
     * `Context.Reference` keys.
     *
     * @see {@link getOption} for a reference-aware optional lookup
     *
     * @stability stable
     * @category getters
     * @since 4.0.0
     */
    <Services, S, I>(self: Context<Services>, key: Key<I, S>): S | undefined;
};
/**
 * Gets the service for a key, throwing if an absent non-reference key cannot be
 * resolved.
 *
 * **When to use**
 *
 * Use when you need to read a service from a context whose type does not prove
 * the service is present.
 *
 * **Details**
 *
 * If the key is a `Context.Reference` and no override is stored in the
 * context, its cached default value is returned. For absent non-reference keys,
 * this function throws a runtime error.
 *
 * **Example** (Getting services unsafely)
 *
 * ```ts import.meta.vitest
 * import { Context, Option } from "effect"
 *
 * const Port = Context.Service<{ PORT: number }>("Port")
 * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
 *
 * const context = Context.make(Port, { PORT: 8080 })
 *
 * Context.getUnsafe(context, Port).PORT // => 8080
 * Context.getOption(context, Timeout) // => Option.none()
 * ```
 *
 * @see {@link get} for type-checked service access
 * @see {@link getOption} for optional service access
 *
 * @stability stable
 * @category unsafe
 * @since 4.0.0
 */
export declare const getUnsafe: {
    /**
     * Gets the service for a key, throwing if an absent non-reference key cannot be
     * resolved.
     *
     * **When to use**
     *
     * Use when you need to read a service from a context whose type does not prove
     * the service is present.
     *
     * **Details**
     *
     * If the key is a `Context.Reference` and no override is stored in the
     * context, its cached default value is returned. For absent non-reference keys,
     * this function throws a runtime error.
     *
     * **Example** (Getting services unsafely)
     *
     * ```ts import.meta.vitest
     * import { Context, Option } from "effect"
     *
     * const Port = Context.Service<{ PORT: number }>("Port")
     * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
     *
     * const context = Context.make(Port, { PORT: 8080 })
     *
     * Context.getUnsafe(context, Port).PORT // => 8080
     * Context.getOption(context, Timeout) // => Option.none()
     * ```
     *
     * @see {@link get} for type-checked service access
     * @see {@link getOption} for optional service access
     *
     * @stability stable
     * @category unsafe
     * @since 4.0.0
     */
    <S, I>(service: Key<I, S>): <Services>(self: Context<Services>) => S;
    /**
     * Gets the service for a key, throwing if an absent non-reference key cannot be
     * resolved.
     *
     * **When to use**
     *
     * Use when you need to read a service from a context whose type does not prove
     * the service is present.
     *
     * **Details**
     *
     * If the key is a `Context.Reference` and no override is stored in the
     * context, its cached default value is returned. For absent non-reference keys,
     * this function throws a runtime error.
     *
     * **Example** (Getting services unsafely)
     *
     * ```ts import.meta.vitest
     * import { Context, Option } from "effect"
     *
     * const Port = Context.Service<{ PORT: number }>("Port")
     * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
     *
     * const context = Context.make(Port, { PORT: 8080 })
     *
     * Context.getUnsafe(context, Port).PORT // => 8080
     * Context.getOption(context, Timeout) // => Option.none()
     * ```
     *
     * @see {@link get} for type-checked service access
     * @see {@link getOption} for optional service access
     *
     * @stability stable
     * @category unsafe
     * @since 4.0.0
     */
    <Services, S, I>(self: Context<Services>, services: Key<I, S>): S;
};
/**
 * Gets a service from the context that corresponds to the given key.
 *
 * **When to use**
 *
 * Use when you need type-checked access to a service already included in the
 * context type.
 *
 * **Example** (Getting a service from a context)
 *
 * ```ts import.meta.vitest
 * import { Context, pipe } from "effect"
 *
 * const Port = Context.Service<{ PORT: number }>("Port")
 * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
 *
 * const context = pipe(
 *   Context.make(Port, { PORT: 8080 }),
 *   Context.add(Timeout, { TIMEOUT: 5000 })
 * )
 *
 * Context.get(context, Timeout).TIMEOUT // => 5000
 * ```
 *
 * @see {@link getOption} for optional service access
 * @see {@link getOrElse} for fallback values
 *
 * @stability stable
 * @category getters
 * @since 2.0.0
 */
export declare const get: {
    /**
     * Gets a service from the context that corresponds to the given key.
     *
     * **When to use**
     *
     * Use when you need type-checked access to a service already included in the
     * context type.
     *
     * **Example** (Getting a service from a context)
     *
     * ```ts import.meta.vitest
     * import { Context, pipe } from "effect"
     *
     * const Port = Context.Service<{ PORT: number }>("Port")
     * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
     *
     * const context = pipe(
     *   Context.make(Port, { PORT: 8080 }),
     *   Context.add(Timeout, { TIMEOUT: 5000 })
     * )
     *
     * Context.get(context, Timeout).TIMEOUT // => 5000
     * ```
     *
     * @see {@link getOption} for optional service access
     * @see {@link getOrElse} for fallback values
     *
     * @stability stable
     * @category getters
     * @since 2.0.0
     */
    <I, S>(service: Key<I, S>): (self: Context<I>) => S;
    /**
     * Gets a service from the context that corresponds to the given key.
     *
     * **When to use**
     *
     * Use when you need type-checked access to a service already included in the
     * context type.
     *
     * **Example** (Getting a service from a context)
     *
     * ```ts import.meta.vitest
     * import { Context, pipe } from "effect"
     *
     * const Port = Context.Service<{ PORT: number }>("Port")
     * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
     *
     * const context = pipe(
     *   Context.make(Port, { PORT: 8080 }),
     *   Context.add(Timeout, { TIMEOUT: 5000 })
     * )
     *
     * Context.get(context, Timeout).TIMEOUT // => 5000
     * ```
     *
     * @see {@link getOption} for optional service access
     * @see {@link getOrElse} for fallback values
     *
     * @stability stable
     * @category getters
     * @since 2.0.0
     */
    <Services, I extends Services, S>(service: Key<I, S>): (self: Context<Services>) => S;
    /**
     * Gets a service from the context that corresponds to the given key.
     *
     * **When to use**
     *
     * Use when you need type-checked access to a service already included in the
     * context type.
     *
     * **Example** (Getting a service from a context)
     *
     * ```ts import.meta.vitest
     * import { Context, pipe } from "effect"
     *
     * const Port = Context.Service<{ PORT: number }>("Port")
     * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
     *
     * const context = pipe(
     *   Context.make(Port, { PORT: 8080 }),
     *   Context.add(Timeout, { TIMEOUT: 5000 })
     * )
     *
     * Context.get(context, Timeout).TIMEOUT // => 5000
     * ```
     *
     * @see {@link getOption} for optional service access
     * @see {@link getOrElse} for fallback values
     *
     * @stability stable
     * @category getters
     * @since 2.0.0
     */
    <Services, I extends Services, S>(self: Context<Services>, service: Key<I, S>): S;
};
/**
 * Gets the service for a key safely wrapped in an `Option`.
 *
 * **When to use**
 *
 * Use when you need to read a `Context` service as an `Option` so absence is
 * represented as data.
 *
 * **Details**
 *
 * Returns `Option.some` when the service is stored in the context. If the key
 * is a `Context.Reference` and no override is stored, returns `Option.some` of
 * the cached default value. Missing non-reference keys return `Option.none`.
 *
 * **Example** (Getting optional services)
 *
 * ```ts import.meta.vitest
 * import { Context, Option } from "effect"
 *
 * const Port = Context.Service<{ PORT: number }>("Port")
 * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
 *
 * const context = Context.make(Port, { PORT: 8080 })
 *
 * Context.getOption(context, Port) // => Option.some({ PORT: 8080 })
 * Context.getOption(context, Timeout) // => Option.none()
 * ```
 *
 * @see {@link getOrElse} for returning a fallback value directly
 *
 * @stability stable
 * @category getters
 * @since 2.0.0
 */
export declare const getOption: {
    /**
     * Gets the service for a key safely wrapped in an `Option`.
     *
     * **When to use**
     *
     * Use when you need to read a `Context` service as an `Option` so absence is
     * represented as data.
     *
     * **Details**
     *
     * Returns `Option.some` when the service is stored in the context. If the key
     * is a `Context.Reference` and no override is stored, returns `Option.some` of
     * the cached default value. Missing non-reference keys return `Option.none`.
     *
     * **Example** (Getting optional services)
     *
     * ```ts import.meta.vitest
     * import { Context, Option } from "effect"
     *
     * const Port = Context.Service<{ PORT: number }>("Port")
     * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
     *
     * const context = Context.make(Port, { PORT: 8080 })
     *
     * Context.getOption(context, Port) // => Option.some({ PORT: 8080 })
     * Context.getOption(context, Timeout) // => Option.none()
     * ```
     *
     * @see {@link getOrElse} for returning a fallback value directly
     *
     * @stability stable
     * @category getters
     * @since 2.0.0
     */
    <S, I>(service: Key<I, S>): <Services>(self: Context<Services>) => Option.Option<S>;
    /**
     * Gets the service for a key safely wrapped in an `Option`.
     *
     * **When to use**
     *
     * Use when you need to read a `Context` service as an `Option` so absence is
     * represented as data.
     *
     * **Details**
     *
     * Returns `Option.some` when the service is stored in the context. If the key
     * is a `Context.Reference` and no override is stored, returns `Option.some` of
     * the cached default value. Missing non-reference keys return `Option.none`.
     *
     * **Example** (Getting optional services)
     *
     * ```ts import.meta.vitest
     * import { Context, Option } from "effect"
     *
     * const Port = Context.Service<{ PORT: number }>("Port")
     * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
     *
     * const context = Context.make(Port, { PORT: 8080 })
     *
     * Context.getOption(context, Port) // => Option.some({ PORT: 8080 })
     * Context.getOption(context, Timeout) // => Option.none()
     * ```
     *
     * @see {@link getOrElse} for returning a fallback value directly
     *
     * @stability stable
     * @category getters
     * @since 2.0.0
     */
    <Services, S, I>(self: Context<Services>, service: Key<I, S>): Option.Option<S>;
};
/**
 * Merges two `Context`s into one.
 *
 * **When to use**
 *
 * Use when you need to combine two contexts.
 *
 * **Details**
 *
 * When both contexts contain the same service key, the service from `that`
 * overrides the service from `self`.
 *
 * **Example** (Merging two contexts)
 *
 * ```ts import.meta.vitest
 * import { Context } from "effect"
 *
 * const Port = Context.Service<{ PORT: number }>("Port")
 * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
 *
 * const firstContext = Context.make(Port, { PORT: 8080 })
 * const secondContext = Context.make(Timeout, { TIMEOUT: 5000 })
 *
 * const context = Context.merge(firstContext, secondContext)
 *
 * const values = [Context.get(context, Port).PORT, Context.get(context, Timeout).TIMEOUT]
 * values // => [8080, 5000]
 * ```
 *
 * @see {@link mergeAll} for merging more than two contexts at once
 *
 * @stability stable
 * @category combining
 * @since 2.0.0
 */
export declare const merge: {
    /**
     * Merges two `Context`s into one.
     *
     * **When to use**
     *
     * Use when you need to combine two contexts.
     *
     * **Details**
     *
     * When both contexts contain the same service key, the service from `that`
     * overrides the service from `self`.
     *
     * **Example** (Merging two contexts)
     *
     * ```ts import.meta.vitest
     * import { Context } from "effect"
     *
     * const Port = Context.Service<{ PORT: number }>("Port")
     * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
     *
     * const firstContext = Context.make(Port, { PORT: 8080 })
     * const secondContext = Context.make(Timeout, { TIMEOUT: 5000 })
     *
     * const context = Context.merge(firstContext, secondContext)
     *
     * const values = [Context.get(context, Port).PORT, Context.get(context, Timeout).TIMEOUT]
     * values // => [8080, 5000]
     * ```
     *
     * @see {@link mergeAll} for merging more than two contexts at once
     *
     * @stability stable
     * @category combining
     * @since 2.0.0
     */
    <R1>(that: Context<R1>): <Services>(self: Context<Services>) => Context<R1 | Services>;
    /**
     * Merges two `Context`s into one.
     *
     * **When to use**
     *
     * Use when you need to combine two contexts.
     *
     * **Details**
     *
     * When both contexts contain the same service key, the service from `that`
     * overrides the service from `self`.
     *
     * **Example** (Merging two contexts)
     *
     * ```ts import.meta.vitest
     * import { Context } from "effect"
     *
     * const Port = Context.Service<{ PORT: number }>("Port")
     * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
     *
     * const firstContext = Context.make(Port, { PORT: 8080 })
     * const secondContext = Context.make(Timeout, { TIMEOUT: 5000 })
     *
     * const context = Context.merge(firstContext, secondContext)
     *
     * const values = [Context.get(context, Port).PORT, Context.get(context, Timeout).TIMEOUT]
     * values // => [8080, 5000]
     * ```
     *
     * @see {@link mergeAll} for merging more than two contexts at once
     *
     * @stability stable
     * @category combining
     * @since 2.0.0
     */
    <Services, R1>(self: Context<Services>, that: Context<R1>): Context<Services | R1>;
};
/**
 * Merges any number of `Context`s into one.
 *
 * **When to use**
 *
 * Use when you need to combine a variadic list of contexts.
 *
 * **Details**
 *
 * When multiple contexts contain the same service key, the service from the
 * last context with that key is kept.
 *
 * **Example** (Merging multiple contexts)
 *
 * ```ts import.meta.vitest
 * import { Context } from "effect"
 *
 * const Port = Context.Service<{ PORT: number }>("Port")
 * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
 * const Host = Context.Service<{ HOST: string }>("Host")
 *
 * const firstContext = Context.make(Port, { PORT: 8080 })
 * const secondContext = Context.make(Timeout, { TIMEOUT: 5000 })
 * const thirdContext = Context.make(Host, { HOST: "localhost" })
 *
 * const context = Context.mergeAll(
 *   firstContext,
 *   secondContext,
 *   thirdContext
 * )
 *
 * context.mapUnsafe.size // => 3
 * ```
 *
 * @see {@link merge} for merging two contexts
 *
 * @stability stable
 * @category combining
 * @since 3.12.0
 */
export declare const mergeAll: <T extends Array<unknown>>(...ctxs: [...{ [K in keyof T]: Context<T[K]>; }]) => Context<T[number]>;
/**
 * Returns a new `Context` that contains only the specified services.
 *
 * **When to use**
 *
 * Use when you want to keep an allowlist of services in a `Context`.
 *
 * **Example** (Picking services from a context)
 *
 * ```ts import.meta.vitest
 * import { Context, Option, pipe } from "effect"
 *
 * const Port = Context.Service<{ PORT: number }>("Port")
 * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
 *
 * const someContext = pipe(
 *   Context.make(Port, { PORT: 8080 }),
 *   Context.add(Timeout, { TIMEOUT: 5000 })
 * )
 *
 * const context = pipe(someContext, Context.pick(Port))
 *
 * Context.getOption(context, Port) // => Option.some({ PORT: 8080 })
 * Context.getOption(context, Timeout) // => Option.none()
 * ```
 *
 * @see {@link omit} for removing selected services
 *
 * @stability stable
 * @category filtering
 * @since 2.0.0
 */
export declare const pick: <S extends ReadonlyArray<Key<any, any>>>(...services: S) => <Services>(self: Context<Services>) => Context<Services & Service.Identifier<S[number]>>;
/**
 * Returns a new `Context` with the specified service keys removed.
 *
 * **When to use**
 *
 * Use when you want to remove a denylist of services from a `Context`.
 *
 * **Example** (Omitting services from a context)
 *
 * ```ts import.meta.vitest
 * import { Context, Option, pipe } from "effect"
 *
 * const Port = Context.Service<{ PORT: number }>("Port")
 * const Timeout = Context.Service<{ TIMEOUT: number }>("Timeout")
 *
 * const someContext = pipe(
 *   Context.make(Port, { PORT: 8080 }),
 *   Context.add(Timeout, { TIMEOUT: 5000 })
 * )
 *
 * const context = pipe(someContext, Context.omit(Timeout))
 *
 * Context.getOption(context, Port) // => Option.some({ PORT: 8080 })
 * Context.getOption(context, Timeout) // => Option.none()
 * ```
 *
 * @see {@link pick} for keeping selected services
 *
 * @stability stable
 * @category filtering
 * @since 2.0.0
 */
export declare const omit: <S extends ReadonlyArray<Key<any, any>>>(...keys: S) => <Services>(self: Context<Services>) => Context<Exclude<Services, Service.Identifier<S[number]>>>;
/**
 * Creates a context key with a default value.
 *
 * **When to use**
 *
 * Use when you need to define a context key with a lazily computed default
 * value.
 *
 * **Details**
 *
 * `Context.Reference` allows you to create a key that can hold a value. You
 * can provide a default value for the service, which will automatically be used
 * when the context is accessed, or override it with a custom implementation
 * when needed. The default value is computed lazily and cached on the
 * reference.
 *
 * **Example** (Creating references with default values)
 *
 * ```ts import.meta.vitest
 * import { Context } from "effect"
 *
 * // Create a reference with a default value
 * const messages: Array<string> = []
 * const LoggerRef = Context.Reference("Logger", {
 *   defaultValue: () => ({ log: (msg: string) => messages.push(`Default: ${msg}`) })
 * })
 *
 * // The reference provides the default value when accessed from an empty context
 * const context = Context.empty()
 * const logger = Context.get(context, LoggerRef)
 *
 * // You can also override the default value
 * const customContext = Context.make(LoggerRef, {
 *   log: (msg: string) => messages.push(`Custom: ${msg}`)
 * })
 * const customLogger = Context.get(customContext, LoggerRef)
 * logger.log("default")
 * customLogger.log("message")
 * messages // => ["Default: default", "Custom: message"]
 * ```
 *
 * @see {@link Service} for required services without default values
 *
 * @stability stable
 * @category services
 * @since 3.11.0
 */
export declare const Reference: <Service>(key: string, options: {
    readonly defaultValue: () => Service;
}) => Reference<Service>;
export {};
//# sourceMappingURL=Context.d.ts.map