Terminal

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import { Terminal } from "@effect/platform"
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import { Effect } from "effect"
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const program = Effect.gen(function* () {
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  const terminal = yield* Terminal.Terminal
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  // Use `terminal` to interact with standard input and output
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})

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import { Terminal } from "@effect/platform"
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import { NodeRuntime, NodeTerminal } from "@effect/platform-node"
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import { Effect } from "effect"
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const program = Effect.gen(function* () {
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  const terminal = yield* Terminal.Terminal
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  yield* terminal.display("a message\n")
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})
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NodeRuntime.runMain(program.pipe(Effect.provide(NodeTerminal.layer)))
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// Output: "a message"

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import { Terminal } from "@effect/platform"
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import { NodeRuntime, NodeTerminal } from "@effect/platform-node"
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import { Effect } from "effect"
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const program = Effect.gen(function* () {
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  const terminal = yield* Terminal.Terminal
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  const input = yield* terminal.readLine
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  console.log(`input: ${input}`)
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})
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NodeRuntime.runMain(program.pipe(Effect.provide(NodeTerminal.layer)))
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// Input: "hello"
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// Output: "input: hello"

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import { Terminal } from "@effect/platform"
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import type { PlatformError } from "@effect/platform/Error"
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import { Effect, Option, Random } from "effect"
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import { NodeRuntime, NodeTerminal } from "@effect/platform-node"
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// Generate a secret random number between 1 and 100
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const secret = Random.nextIntBetween(1, 100)
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// Parse the user's input into a valid number
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const parseGuess = (input: string) => {
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  const n = parseInt(input, 10)
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  return isNaN(n) || n < 1 || n > 100 ? Option.none() : Option.some(n)
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}
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// Display a message on the terminal
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const display = (message: string) =>
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  Effect.gen(function* () {
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    const terminal = yield* Terminal.Terminal
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    yield* terminal.display(`${message}\n`)
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  })
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// Prompt the user for a guess
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const prompt = Effect.gen(function* () {
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  const terminal = yield* Terminal.Terminal
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  yield* terminal.display("Enter a guess: ")
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  return yield* terminal.readLine
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})
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// Get the user's guess, validating it as an integer between 1 and 100
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const answer: Effect.Effect<number, Terminal.QuitException | PlatformError, Terminal.Terminal> =
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  Effect.gen(function* () {
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    const input = yield* prompt
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    const guess = parseGuess(input)
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    if (Option.isNone(guess)) {
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      yield* display("You must enter an integer from 1 to 100")
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      return yield* answer
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    }
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    return guess.value
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  })
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// Check if the guess is too high, too low, or correct
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const check = <A, E, R>(
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  secret: number,
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  guess: number,
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  ok: Effect.Effect<A, E, R>,
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  ko: Effect.Effect<A, E, R>,
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) =>
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  Effect.gen(function* () {
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    if (guess > secret) {
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      yield* display("Too high")
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      return yield* ko
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    } else if (guess < secret) {
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      yield* display("Too low")
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      return yield* ko
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    } else {
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      return yield* ok
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    }
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  })
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// End the game with a success message
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const end = display("You guessed it!")
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// Main game loop
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const loop = (
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  secret: number,
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): Effect.Effect<void, Terminal.QuitException | PlatformError, Terminal.Terminal> =>
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  Effect.gen(function* () {
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    const guess = yield* answer
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    return yield* check(
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      secret,
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      guess,
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      end,
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      Effect.suspend(() => loop(secret)),
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    )
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  })
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// Full game setup and execution
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const game = Effect.gen(function* () {
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  yield* display(
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    `We have selected a random number between 1 and 100.
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See if you can guess it in 10 turns or fewer.
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We'll tell you if your guess was too high or too low.`,
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  )
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  yield* loop(yield* secret)
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})
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// Run the game
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NodeRuntime.runMain(game.pipe(Effect.provide(NodeTerminal.layer)))