"Unexpected end of input" error, which is unexpected to me

Hello, I am working currently with effekt 0.10.0 and the vscode extension 0.2.3. So I am working in the homework 4 repo at the file pull.effekt.md which contains the following content. The extension shows no syntax error and i didnt changed anything (so i assume that the syntax should be right), but when i try to import the file in the repl i get this error:

[error] 1:5: Unexpected end of input
import tasks/pull.effekt.md

Sometimes the extension marks the last closing literate symbols ``` as wrong input.

Would love to get some help.

Greetings Micha

Source: pull.effekt.md

``````markdown ```effekt module pull import test import tasks/utils/test import char ``` In this task, we'll play with pull streams. Here are some effect definitions: ```effekt /// Signal from a producer to a consumer that there are no further values. /// = early exit effect stop(): Nothing /// emit (push stream): emits/produces values of type `A` /// = producer /// /// (you already know these!) effect emit[A](value: A): Unit /// read (pull stream): requires values of type `A` /// = consumer /// /// The producer can decide to `stop` emitting values! /// => bidirectional! effect read[A]() : A / stop ``` ### Part 1: Write `feed` on `List`s: Notice that the resume takes a computation now, `read` is a bidirectional effect (which means that we can call `stop` inside!) ```effekt def feed[T](list: List[T]) { reader: () => Unit / read[T] } = { var l = list try { reader() } with read[T] { resume { do stop() // TODO: // Instead of always stopping, stop only if `l` is `Nil()` // Otherwise if it's a Cons, set `l` to the tail and return the head } } } ``` ### Part 2: Write `feed` on `String`s: ```effekt // Same as above, but for strings. // Use 'string.length' and 'string.unsafeCharAt(index)' def feed(string: String) { reader: () => Unit / read[Char] } = { var index = 0 try { reader() } with read[Char] { () // TODO: this time try yourself } } ``` ### Intermezzo: a few functions using pull and push streams! Here are some functions that use `read` (pull streams) and `emit` (push streams). Take a closer look! ```effekt /// Reads a positive number from the pull stream. def readPositive(base: Int): Int / { read[Char], Exception[WrongFormat] } = { var res: Int = try char::digitValue(do read()) with stop { wrongFormat("Positive number should start with a digit!") } def go(): Int = try { val d = char::digitValue(do read(), base) res = res * base + d go() } with stop { res } with Exception[WrongFormat] { def raise(e, m) = res } go() } /// Runs a `program` until it `stop`s, applying `action` onto every value recieved from `program`. /// Useful in combination with pull streams. def untilStopDo[A] { program: () => A / stop } { action: A => Unit }: Unit = try { def go(): Unit = { action(program()) go() } go() } with stop { def stop() = () } def each[A](list: List[A]): Unit / emit[A] = list match { case Nil() => () case Cons(head, tail) => do emit(head) each(tail) } def each(string: String): Unit / emit[Char] = feed(string) { untilStopDo[Char] { do read() } { char => do emit(char) } } ``` #### Example: parsing Here's a quick example of `feed` on `String`s, featuring `readPositive`! ```effekt def example() = { with on[WrongFormat].panic feed("1111111+99999999") { val n = readPositive(10) println("n = " ++ n.show) // note that this call eats up the `+` as a side effect val m = readPositive(10) println("m = " ++ m.show) println("n + m = " ++ show(n + m)) } } ``` ### Part 3: What does `source` do? Try to describe what the following function does and write an example: You already know `emit` from previous tasks. Feel free to write/copy some functions that use it. Hint: let the types guide you, take a closer look, hover over things, turn on captures, etc.! `:)` ```effekt def whatDoesSourceDo(): String = "" // TODO def sourceExample() = () def source[A, R] { stream: () => Unit / emit[A] } { reader: () => R / read[A] }: R = { var next = box { None() } next = box { try { stream() None() } with emit[A] { (v) => next = box { resume(()) } Some(v) } } try { reader() } with read[A] { resume { next().getOrElse { do stop() } } } } ``` ### Main and tests When you're done with this task, put something in the `done` variable below to make the test pass. ```effekt def done(): String = "" // TODO: when you're done, set this to something non-empty :) def main() = example() ``` #### Tests ```effekt def testSuite() = suite("tasks/pull") { test("feed (list): nonempty exhaustive") { var result = [] feed([1, 2, 3]) { untilStopDo { do read[Int] } { v => result = Cons(v, result) } } assertEqual(result, [3, 2, 1]) } test("feed (list): empty exhaustive") { var result = [] feed(Nil[Int]()) { untilStopDo { do read[Int] } { v => result = Cons(v, result) } } assertEqual(result, []) } test("feed (list): nonempty non-exhaustive 1") { var opt: Option[Int] = None() feed([1, 2, 3]) { try { opt = Some(do read()) } with stop { () } } assertEqual(opt, Some(1)) } test("feed (list): nonempty non-exhaustive 2") { def getTwo() = { val left = do read[Int]() val right = do read[Int]() (left, right) } var opt: Option[(Int, Int)] = None() feed([10, 20, 100]) { try { opt = Some(getTwo()) } with stop { () } } assertEqual(opt.map { case (l, r) => l + r }, Some(30)) } test("feed (list): empty non-exhaustive") { var opt: Option[Int] = None() feed(Nil[Int]()) { try { opt = Some(do read()) } with stop { () } } assertEqual(opt, None()) } test("feed (string): 111+222") { with on[WrongFormat].panic var res = 0 feed("111+222") { val n = readPositive(10) val m = readPositive(10) res = n + m } assert(res, 333) } test("what does source do?") { assertNonempty(whatDoesSourceDo()) } test("done?") { assertNonempty(done()) } } ``` ``````

effekt-lang / effekt

"Unexpected end of input" error, which is unexpected to me #699