temp commit

orchid-host/src/ctx.rs

@@ -3,7 +3,6 @@ use std::num::{NonZero, NonZeroU16};
 use std::rc::{Rc, Weak};
 use std::{fmt, ops};
 
-use async_once_cell::OnceCell;
 use async_std::sync::RwLock;
 use hashbrown::HashMap;
 use orchid_api::SysId;
@@ -13,17 +12,17 @@ use orchid_base::interner::Interner;
 use crate::api;
 use crate::atom::WeakAtomHand;
 use crate::expr_store::ExprStore;
-use crate::parsed::Root;
 use crate::system::{System, WeakSystem};
+use crate::tree::WeakRoot;
 
 pub struct CtxData {
-	pub i: Rc<Interner>,
+	pub i: Interner,
 	pub spawn: Spawner,
 	pub systems: RwLock<HashMap<api::SysId, WeakSystem>>,
 	pub system_id: RefCell<NonZeroU16>,
 	pub owned_atoms: RwLock<HashMap<api::AtomId, WeakAtomHand>>,
 	pub common_exprs: ExprStore,
-	pub root: OnceCell<Weak<Root>>,
+	pub root: RwLock<WeakRoot>,
 }
 #[derive(Clone)]
 pub struct Ctx(Rc<CtxData>);
@@ -31,30 +30,39 @@ impl ops::Deref for Ctx {
 	type Target = CtxData;
 	fn deref(&self) -> &Self::Target { &self.0 }
 }
+#[derive(Clone)]
+pub struct WeakCtx(Weak<CtxData>);
+impl WeakCtx {
+	#[must_use]
+	pub fn try_upgrade(&self) -> Option<Ctx> { Some(Ctx(self.0.upgrade()?)) }
+	#[must_use]
+	pub fn upgrade(&self) -> Ctx { self.try_upgrade().expect("Ctx manually kept alive until exit") }
+}
 impl Ctx {
+	#[must_use]
 	pub fn new(spawn: Spawner) -> Self {
 		Self(Rc::new(CtxData {
 			spawn,
-			i: Rc::default(),
+			i: Interner::default(),
 			systems: RwLock::default(),
 			system_id: RefCell::new(NonZero::new(1).unwrap()),
 			owned_atoms: RwLock::default(),
 			common_exprs: ExprStore::default(),
-			root: OnceCell::default(),
+			root: RwLock::default(),
 		}))
 	}
+	#[must_use]
 	pub(crate) async fn system_inst(&self, id: api::SysId) -> Option<System> {
 		self.systems.read().await.get(&id).and_then(WeakSystem::upgrade)
 	}
+	#[must_use]
 	pub(crate) fn next_sys_id(&self) -> api::SysId {
 		let mut g = self.system_id.borrow_mut();
 		*g = g.checked_add(1).unwrap_or(NonZeroU16::new(1).unwrap());
 		SysId(*g)
 	}
-	pub async fn set_root(&self, root: Weak<Root>) {
-		assert!(self.root.get().is_none(), "Root already assigned");
-		self.root.get_or_init(async { root }).await;
-	}
+	#[must_use]
+	pub fn downgrade(&self) -> WeakCtx { WeakCtx(Rc::downgrade(&self.0)) }
 }
 impl fmt::Debug for Ctx {
 	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {