/** * @since 2.0.0 */ import type * as Array from "./Array.js" import type * as Cause from "./Cause.js" import type * as Chunk from "./Chunk.js" import type * as Context from "./Context.js" import type * as Effect from "./Effect.js" import * as defaultServices from "./internal/defaultServices.js" import * as internal from "./internal/random.js" import type * as NonEmptyIterable from "./NonEmptyIterable.js" /** * @since 2.0.0 * @category symbols */ export const RandomTypeId: unique symbol = internal.RandomTypeId /** * @since 2.0.0 * @category symbols */ export type RandomTypeId = typeof RandomTypeId /** * @since 2.0.0 * @category models */ export interface Random { readonly [RandomTypeId]: RandomTypeId /** * Returns the next numeric value from the pseudo-random number generator. */ readonly next: Effect.Effect /** * Returns the next boolean value from the pseudo-random number generator. */ readonly nextBoolean: Effect.Effect /** * Returns the next integer value from the pseudo-random number generator. */ readonly nextInt: Effect.Effect /** * Returns the next numeric value in the specified range from the * pseudo-random number generator. */ nextRange(min: number, max: number): Effect.Effect /** * Returns the next integer value in the specified range from the * pseudo-random number generator. */ nextIntBetween(min: number, max: number): Effect.Effect /** * Uses the pseudo-random number generator to shuffle the specified iterable. */ shuffle(elements: Iterable): Effect.Effect> } /** * Returns the next numeric value from the pseudo-random number generator. * * @since 2.0.0 * @category constructors */ export const next: Effect.Effect = defaultServices.next /** * Returns the next integer value from the pseudo-random number generator. * * @since 2.0.0 * @category constructors */ export const nextInt: Effect.Effect = defaultServices.nextInt /** * Returns the next boolean value from the pseudo-random number generator. * * @since 2.0.0 * @category constructors */ export const nextBoolean: Effect.Effect = defaultServices.nextBoolean /** * Returns the next numeric value in the specified range from the * pseudo-random number generator. * * @since 2.0.0 * @category constructors */ export const nextRange: (min: number, max: number) => Effect.Effect = defaultServices.nextRange /** * Returns the next integer value in the specified range from the * pseudo-random number generator. * * @since 2.0.0 * @category constructors */ export const nextIntBetween: (min: number, max: number) => Effect.Effect = defaultServices.nextIntBetween /** * Uses the pseudo-random number generator to shuffle the specified iterable. * * @since 2.0.0 * @category constructors */ export const shuffle: (elements: Iterable) => Effect.Effect> = defaultServices.shuffle /** * Get a random element from an iterable. * * @example * ```ts * import { Effect, Random } from "effect" * * Effect.gen(function* () { * const randomItem = yield* Random.choice([1, 2, 3]) * console.log(randomItem) * }) * ``` * * @since 3.6.0 * @category constructors */ export const choice: >( elements: Self ) => Self extends NonEmptyIterable.NonEmptyIterable ? Effect.Effect : Self extends Array.NonEmptyReadonlyArray ? Effect.Effect : Self extends Iterable ? Effect.Effect : never = defaultServices.choice /** * Retreives the `Random` service from the context and uses it to run the * specified workflow. * * @since 2.0.0 * @category constructors */ export const randomWith: (f: (random: Random) => Effect.Effect) => Effect.Effect = defaultServices.randomWith /** * @since 2.0.0 * @category context */ export const Random: Context.Tag = internal.randomTag /** * Constructs the `Random` service, seeding the pseudo-random number generator * with an hash of the specified seed. * This constructor is useful for generating predictable sequences of random values for specific use cases. * * Example uses: * - Generating random UI data for visual tests. * - Creating data that needs to change daily but remain the same throughout a single day, such as using a date as the seed. * * @example * ```ts * import * as assert from "node:assert" * import { Effect, Random } from "effect" * * const random1 = Random.make("myseed") * const random2 = Random.make("myseed") * * assert.equal(Effect.runSync(random1.next), Effect.runSync(random2.next)) * ``` * * @since 3.5.0 * @category constructors */ export const make: (seed: A) => Random = internal.make /** * Constructs the `Random` service from an array of literal values. * The service will cycle through the provided values in order when generating random values. * This constructor is useful for creating deterministic sequences for testing or when specific values need to be returned. * * @example * ```ts * import { Effect, Random } from "effect" * * Effect.gen(function* () { * console.log(yield* Random.next) // 0.2 * console.log(yield* Random.next) // 0.5 * console.log(yield* Random.next) // 0.8 * console.log(yield* Random.next) // 0.2 (cycles back) * }).pipe(Effect.withRandom(Random.fixed([0.2, 0.5, 0.8]))) * ``` * * @example * ```ts * import { Effect, Random } from "effect" * * Effect.gen(function* () { * console.log(yield* Random.nextBoolean) // true * console.log(yield* Random.nextBoolean) // false * console.log(yield* Random.nextBoolean) // true * }).pipe(Effect.withRandom(Random.fixed([true, false, true]))) * ``` * * @since 3.11.0 * @category constructors */ export const fixed: >(values: T) => Random = internal.fixed