Added Thread class to stdlib. (0.21.3)

lib/io/thread.fun

@@ -0,0 +1,39 @@
+/*
+ * This file is part of the Fun programming language.
+ * https://hanez.org/project/fun/
+ *
+ * Copyright 2025 Johannes Findeisen
+ * Licensed under the terms of the Apache-2.0 license.
+ * https://opensource.org/license/apache-2-0
+ *
+ * Added: 2025-10-04
+ */
+
+/*
+ * Thread utilities built on thread_spawn() and thread_join().
+ *
+ * Methods:
+ *   spawn(func, args) -> thread id number (args may be a single value or an array of values)
+ *   join(id) -> returns the thread function's return value
+ *
+ * Convenience aliases:
+ *   start(func, args) -> same as spawn()
+ *   wait(id) -> same as join()
+ */
+
+class Thread()
+  // Spawn a new thread running function `func` with `args`.
+  // `args` can be a single argument or an array of arguments for the function.
+  fun spawn(this, func, args)
+    return thread_spawn(func, args)
+
+  // Join a thread by id and get its return value.
+  fun join(this, id)
+    return thread_join(id)
+
+  // Aliases for readability
+  fun start(this, func, args)
+    return thread_spawn(func, args)
+
+  fun wait(this, id)
+    return thread_join(id)