1 files changed, 47 insertions, 0 deletions
diff --git a/src/thread/scope.rst b/src/thread/scope.rst
new file mode 100644
index 0000000..09319cb
--- /dev/null
+++ b/src/thread/scope.rst
@@ -0,0 +1,47 @@
+use std::marker::PhantomData;
+
+use crate::{Keyable, ThreadKey};
+
+use super::{Scope, ScopedJoinHandle};
+
+pub fn scope<'env, F, T>(key: impl Keyable, f: F) -> T
+where
+	F: for<'scope> FnOnce(&'scope Scope<'scope, 'env>) -> T,
+{
+	let scope = Scope(PhantomData);
+	let t = f(&scope);
+	drop(key);
+	t
+}
+
+impl<'scope> Scope<'scope, '_> {
+	#[allow(clippy::unused_self)]
+	pub fn spawn<T: Send + 'scope>(
+		&self,
+		f: impl FnOnce(ThreadKey) -> T + Send + 'scope,
+	) -> std::io::Result<ScopedJoinHandle<'scope, T>> {
+		unsafe {
+			// safety: the lifetimes ensure that the data lives long enough
+			let handle = std::thread::Builder::new().spawn_unchecked(|| {
+				// safety: the thread just started, so the key cannot be acquired yet
+				let key = ThreadKey::get().unwrap_unchecked();
+				f(key)
+			})?;
+
+			Ok(ScopedJoinHandle {
+				handle,
+				_phantom: PhantomData,
+			})
+		}
+	}
+}
+
+impl<T> ScopedJoinHandle<'_, T> {
+	pub fn is_finished(&self) -> bool {
+		self.handle.is_finished()
+	}
+
+	pub fn join(self) -> std::thread::Result<T> {
+		self.handle.join()
+	}
+}