refactor(m323): per-directory BUILDs, drop dir spaces, add Scala app

- Rename "Aufgabe 5"->Aufgabe5 and "Aufgabe 6"->Aufgabe6; spaces broke
  bazel run (Aspect URL-encoding, scala/JVM launcher self-path).
- Per-directory BUILD.bazel: Aufgabe5 (swift_binary), Aufgabe6 (swift_binary).
- Aufgabe6/Third: Scala app via rules_scala (scala_library + scala_binary).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Sources/Aufgabe 5/main.swift

@@ -1,29 +0,0 @@
-import Foundation
-
-let weatherData: [(city: String, description: String, temperature: Double)] = [
-    (city: "Zurich", description: "cloudy", temperature: 18.5),
-    (city: "Bern", description: "sunny", temperature: 22.1),
-    (city: "Geneva", description: "rainy", temperature: 15.3),
-    (city: "Basel", description: "sunny", temperature: 24.7),
-    (city: "Lucerne", description: "foggy", temperature: 11.0),
-    (city: "Lugano", description: "sunny", temperature: 31.2),
-    (city: "Lausanne", description: "cloudy", temperature: 19.8),
-    (city: "Chur", description: "snowing", temperature: -2.5),
-    (city: "Davos", description: "snowing", temperature: -5.1),
-    (city: "Locarno", description: "thunderstorm", temperature: 27.4),
-]
-
-func weatherStation(city: String, description: String, temperature: Double) -> (
-    String, String, Double
-)? {
-    if temperature >= 20 {
-        let dateTimeString = Date.now.formatted(date: .abbreviated, time: .shortened)
-        return (description, dateTimeString, temperature)
-    } else {
-        return nil
-    }
-}
-
-for weather in weatherData {
-    weatherStation(city: weather.0, description: weather.1, temperature: weather.2)
-}

Sources/Aufgabe5/BUILD.bazel

@@ -1,7 +1,7 @@
 load("@rules_swift//swift:swift.bzl", "swift_binary")
 
 # Per-directory BUILD: define targets where their sources live, then reference
-# them by label (e.g. //Sources/Aufgabe 5:Aufgabe5) from elsewhere to keep the
+# them by label (e.g. //m323/Sources/Aufgabe5:Aufgabe5) from elsewhere to keep the
 # top-level BUILD.bazel uncluttered.
 swift_binary(
     name = "Aufgabe5",

Sources/Aufgabe5/main.swift

@@ -0,0 +1,29 @@
+import Foundation
+
+let weatherData: [(city: String, description: String, temperature: Double)] = [
+  (city: "Zurich", description: "cloudy", temperature: 18.5),
+  (city: "Bern", description: "sunny", temperature: 22.1),
+  (city: "Geneva", description: "rainy", temperature: 15.3),
+  (city: "Basel", description: "sunny", temperature: 24.7),
+  (city: "Lucerne", description: "foggy", temperature: 11.0),
+  (city: "Lugano", description: "sunny", temperature: 31.2),
+  (city: "Lausanne", description: "cloudy", temperature: 19.8),
+  (city: "Chur", description: "snowing", temperature: -2.5),
+  (city: "Davos", description: "snowing", temperature: -5.1),
+  (city: "Locarno", description: "thunderstorm", temperature: 27.4),
+]
+
+func weatherStation(city: String, description: String, temperature: Double) -> (
+  String, String, Double
+)? {
+  if temperature >= 20 {
+    let dateTimeString = Date.now.formatted(date: .abbreviated, time: .shortened)
+    return (description, dateTimeString, temperature)
+  } else {
+    return nil
+  }
+}
+
+for weather in weatherData {
+  weatherStation(city: weather.0, description: weather.1, temperature: weather.2)
+}

Sources/Aufgabe6/BUILD.bazel

@@ -0,0 +1,7 @@
+load("@rules_swift//swift:swift.bzl", "swift_binary")
+
+swift_binary(
+    name = "Aufgabe6",
+    srcs = ["main.swift","first.swift", "second.swift"],
+    visibility = ["//visibility:public"],
+)

Sources/Aufgabe6/Third/BUILD.bazel

@@ -0,0 +1,15 @@
+load("@rules_scala//scala:scala.bzl", "scala_binary", "scala_library")
+
+# Reusable library; reference it by label from other BUILD files.
+scala_library(
+    name = "runner",
+    srcs = ["Runner.scala"],
+    visibility = ["//visibility:public"],
+)
+
+# Runnable: bazel run //m323/Sources/Aufgabe6/Third:app
+scala_binary(
+    name = "app",
+    main_class = "Runner",
+    deps = [":runner"],
+)

Sources/Aufgabe6/Third/Runner.scala

@@ -0,0 +1,6 @@
+object Runner {
+  def main(args: Array[String]) = {
+    val naturals = LazyList.from(1)
+    println(naturals.take(8).toList)
+  }
+}

Sources/Aufgabe6/first.swift

@@ -0,0 +1,46 @@
+import Foundation
+
+class Course {
+  let name: String
+  let students: [String]
+
+  init(name: String, students: [String]) {
+    self.name = name
+    self.students = students
+  }
+}
+
+let courses = [
+  Course(name: "M323", students: ["Peter", "Petra", "Paul", "Paula"]),
+  Course(name: "M183", students: ["Paula", "Franz", "Franziska"]),
+  Course(name: "M117", students: ["Paul", "Paula"]),
+  Course(name: "M114", students: ["Petra", "Paul", "Paula"]),
+]
+
+// print(
+//     courses.map {
+//         return $0.students
+//     }.filter {
+//         $0.contains("Peter")
+//     }.count
+// )
+
+// print(
+//     courses.map {
+//         return $0.students
+//     }.filter {
+//         $0.contains("Petra")
+//     }.count
+// )
+
+func studentAttendsCourse(studentName: String, courses: [Course]) -> String {
+  let visitedCourses = courses.map {
+    return ($0.name, $0.students)
+  }.filter {
+    $0.1.contains(studentName)
+  }.map {
+    return $0.0
+  }
+  return
+    "\(studentName) visits the following courses: \(visitedCourses.joined(separator: ", "))"
+}

Sources/Aufgabe6/main.swift

@@ -0,0 +1,7 @@
+import Foundation
+
+print(studentAttendsCourse(studentName: "Petra", courses: courses))
+print(studentAttendsCourse(studentName: "Peter", courses: courses))
+
+let result = allowedToLeaveHome().unsafeRun()
+print("Allowed to leave home: \(result)")

Sources/Aufgabe6/second.swift

@@ -0,0 +1,29 @@
+// IO monad: wraps a thunk (deferred computation)
+struct IO<A> {
+  private let effect: () -> A
+
+  init(_ effect: @escaping () -> A) {
+    self.effect = effect
+  }
+
+  // Transform the result without executing
+  func map<B>(_ f: @escaping (A) -> B) -> IO<B> {
+    IO<B> { f(self.effect()) }
+  }
+
+  func unsafeRun() -> A {
+    effect()
+  }
+}
+
+func rollDiceImpure() -> Int {
+  return Int.random(in: 1...6)
+}
+
+func rollDice() -> IO<Int> {
+  IO { rollDiceImpure() }
+}
+
+func allowedToLeaveHome() -> IO<Bool> {
+  rollDice().map { $0 == 6 }
+}