Stream.range — API

Stream.rangeconsteffect/Stream.ts:1757

(min: number, max: number, chunkSize?: number): Stream<number>

Constructs a stream from a range of integers, including both endpoints.

Details

If the provided min is greater than max, the stream will not emit any values.

Example (Creating a numeric range)

import { Console, Effect, Stream } from "effect"

const program = Effect.gen(function*() {
  const values = yield* Stream.range(1, 5).pipe(Stream.runCollect)
  yield* Console.log(values)
})

Effect.runPromise(program)
// Output: [ 1, 2, 3, 4, 5 ]

constructors

Source effect/Stream.ts:175721 lines

export const range = (
  min: number,
  max: number,
  chunkSize = Channel.DefaultChunkSize
): Stream<number> =>
  min > max ? empty : fromPull(Effect.sync(() => {
    let start = min
    let done = false
    return Effect.suspend(() => {
      if (done) return Cause.done()
      const remaining = max - start + 1
      if (remaining > chunkSize) {
        const chunk = Arr.range(start, start + chunkSize - 1)
        start += chunkSize
        return Effect.succeed(chunk)
      }
      const chunk = Arr.range(start, start + remaining - 1)
      done = true
      return Effect.succeed(chunk)
    })
  }))