Correctly halts

orchid-api/Cargo.toml

@@ -10,6 +10,7 @@ ordered-float = "5.0.0"
 orchid-api-traits = { version = "0.1.0", path = "../orchid-api-traits" }
 orchid-api-derive = { version = "0.1.0", path = "../orchid-api-derive" }
 futures = { version = "0.3.31", features = ["std"], default-features = false }
+itertools = "0.14.0"
 
 [dev-dependencies]
 test_executors = "0.3.2"

orchid-api/src/atom.rs

@@ -1,14 +1,28 @@
+use std::fmt;
 use std::num::NonZeroU64;
 
+use itertools::Itertools;
 use orchid_api_derive::{Coding, Hierarchy};
 use orchid_api_traits::Request;
 
 use crate::{
-	ExprTicket, Expression, ExtHostReq, FormattingUnit, HostExtNotif, HostExtReq, OrcResult, SysId,
-	TStrv,
+	ExprTicket, Expression, ExtHostReq, FormattingUnit, HostExtReq, OrcResult, SysId, TStrv,
 };
 
-pub type AtomData = Vec<u8>;
+#[derive(Clone, Coding)]
+pub struct AtomData(pub Vec<u8>);
+impl fmt::Debug for AtomData {
+	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+		let mut byte_strings = self.0.iter().map(|b| format!("{b:02x}"));
+		if self.0.len() < 32 {
+			write!(f, "AtomData({})", byte_strings.join(" "))
+		} else {
+			let data_table =
+				byte_strings.chunks(32).into_iter().map(|mut chunk| chunk.join(" ")).join("\n");
+			write!(f, "AtomData(\n{}\n)", data_table)
+		}
+	}
+}
 
 /// Unique ID associated with atoms that have an identity
 #[derive(Clone, Copy, Debug, Hash, PartialEq, Eq, PartialOrd, Ord, Coding)]
@@ -16,7 +30,7 @@ pub struct AtomId(pub NonZeroU64);
 
 /// An atom owned by an implied system. Usually used in responses from a system.
 /// This has the same semantics as [Atom] except in that the owner is implied.
-#[derive(Clone, Debug, Hash, PartialEq, Eq, Coding)]
+#[derive(Clone, Debug, Coding)]
 pub struct LocalAtom {
 	pub drop: Option<AtomId>,
 	pub data: AtomData,
@@ -27,7 +41,7 @@ impl LocalAtom {
 
 /// An atom representation that can be serialized and sent around. Atoms
 /// represent the smallest increment of work.
-#[derive(Clone, Debug, Hash, PartialEq, Eq, Coding)]
+#[derive(Clone, Debug, Coding)]
 pub struct Atom {
 	/// Instance ID of the system that created the atom
 	pub owner: SysId,
@@ -49,7 +63,7 @@ pub struct Atom {
 }
 
 /// Attempt to apply an atom as a function to an expression
-#[derive(Clone, Debug, Hash, PartialEq, Eq, Coding, Hierarchy)]
+#[derive(Clone, Debug, Coding, Hierarchy)]
 #[extends(AtomReq, HostExtReq)]
 pub struct CallRef(pub Atom, pub ExprTicket);
 impl Request for CallRef {
@@ -59,14 +73,14 @@ impl Request for CallRef {
 /// Attempt to apply an atom as a function, consuming the atom and enabling the
 /// library to reuse its datastructures rather than duplicating them. This is an
 /// optimization over [CallRef] followed by [AtomDrop].
-#[derive(Clone, Debug, Hash, PartialEq, Eq, Coding, Hierarchy)]
+#[derive(Clone, Debug, Coding, Hierarchy)]
 #[extends(AtomReq, HostExtReq)]
 pub struct FinalCall(pub Atom, pub ExprTicket);
 impl Request for FinalCall {
 	type Response = Expression;
 }
 
-#[derive(Clone, Debug, Hash, PartialEq, Eq, Coding, Hierarchy)]
+#[derive(Clone, Debug, Coding, Hierarchy)]
 #[extends(AtomReq, HostExtReq)]
 pub struct SerializeAtom(pub Atom);
 impl Request for SerializeAtom {
@@ -81,14 +95,14 @@ impl Request for DeserAtom {
 }
 
 /// A request blindly routed to the system that provides an atom.
-#[derive(Clone, Debug, Hash, PartialEq, Eq, Coding, Hierarchy)]
+#[derive(Clone, Debug, Coding, Hierarchy)]
 #[extends(AtomReq, HostExtReq)]
 pub struct Fwded(pub Atom, pub TStrv, pub Vec<u8>);
 impl Request for Fwded {
 	type Response = Option<Vec<u8>>;
 }
 
-#[derive(Clone, Debug, Hash, PartialEq, Eq, Coding, Hierarchy)]
+#[derive(Clone, Debug, Coding, Hierarchy)]
 #[extends(ExtHostReq)]
 pub struct Fwd(pub Atom, pub TStrv, pub Vec<u8>);
 impl Request for Fwd {
@@ -100,7 +114,7 @@ pub enum NextStep {
 	Continue(Expression),
 	Halt,
 }
-#[derive(Clone, Debug, Hash, PartialEq, Eq, Coding, Hierarchy)]
+#[derive(Clone, Debug, Coding, Hierarchy)]
 #[extends(AtomReq, HostExtReq)]
 pub struct Command(pub Atom);
 impl Request for Command {
@@ -111,17 +125,20 @@ impl Request for Command {
 /// isn't referenced anywhere. This should have no effect if the atom's `drop`
 /// flag is false.
 #[derive(Clone, Debug, Hash, PartialEq, Eq, Coding, Hierarchy)]
-#[extends(HostExtNotif)]
+#[extends(HostExtReq)]
 pub struct AtomDrop(pub SysId, pub AtomId);
+impl Request for AtomDrop {
+	type Response = ();
+}
 
-#[derive(Clone, Debug, Hash, PartialEq, Eq, Coding, Hierarchy)]
+#[derive(Clone, Debug, Coding, Hierarchy)]
 #[extends(AtomReq, HostExtReq)]
 pub struct AtomPrint(pub Atom);
 impl Request for AtomPrint {
 	type Response = FormattingUnit;
 }
 
-#[derive(Clone, Debug, Hash, PartialEq, Eq, Coding, Hierarchy)]
+#[derive(Clone, Debug, Coding, Hierarchy)]
 #[extends(ExtHostReq)]
 pub struct ExtAtomPrint(pub Atom);
 impl Request for ExtAtomPrint {
@@ -129,7 +146,7 @@ impl Request for ExtAtomPrint {
 }
 
 /// Requests that apply to an existing atom instance
-#[derive(Clone, Debug, Hash, PartialEq, Eq, Coding, Hierarchy)]
+#[derive(Clone, Debug, Coding, Hierarchy)]
 #[extends(HostExtReq)]
 #[extendable]
 pub enum AtomReq {

orchid-api/src/expr.rs

@@ -1,3 +1,4 @@
+use std::fmt;
 use std::num::NonZeroU64;
 
 use orchid_api_derive::{Coding, Hierarchy};
@@ -10,8 +11,13 @@ use crate::{Atom, ExtHostNotif, ExtHostReq, Location, OrcError, SysId, TStrv};
 /// [Acquire].
 ///
 /// The ID is globally unique within its lifetime, but may be reused.
-#[derive(Copy, Clone, Debug, Hash, PartialEq, Eq, PartialOrd, Ord, Coding)]
+#[derive(Copy, Clone, Hash, PartialEq, Eq, PartialOrd, Ord, Coding)]
 pub struct ExprTicket(pub NonZeroU64);
+impl fmt::Debug for ExprTicket {
+	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+		write!(f, "ExprTicket({:x})", self.0.get())
+	}
+}
 
 /// Acquire a strong reference to an expression. This keeps it alive until a
 /// corresponding [Release] is emitted. The number of times a system has
@@ -62,7 +68,7 @@ pub enum ExpressionKind {
 	Arg(u64),
 	/// Insert the specified host-expression in the template here. When the clause
 	/// is used in the const tree, this variant is forbidden.
-	Slot(ExprTicket),
+	Slot { tk: ExprTicket, by_value: bool },
 	/// The lhs must be fully processed before the rhs can be processed.
 	/// Equivalent to Haskell's function of the same name
 	Seq(Box<Expression>, Box<Expression>),

orchid-api/src/parser.rs

@@ -68,10 +68,7 @@ pub enum ParsedMemberKind {
 /// the macro engine could run here.
 #[derive(Clone, Debug, Coding, Hierarchy)]
 #[extends(HostExtReq)]
-pub struct FetchParsedConst {
-	pub sys: SysId,
-	pub id: ParsedConstId,
-}
+pub struct FetchParsedConst(pub SysId, pub ParsedConstId);
 impl Request for FetchParsedConst {
 	type Response = Expression;
 }

orchid-api/src/proto.rs

@@ -120,14 +120,14 @@ pub enum HostExtReq {
 	ParseLine(parser::ParseLine),
 	FetchParsedConst(parser::FetchParsedConst),
 	GetMember(tree::GetMember),
+	SystemDrop(system::SystemDrop),
+	AtomDrop(atom::AtomDrop),
 }
 
 /// Notifications sent from the host to the extension
 #[derive(Clone, Debug, Coding, Hierarchy)]
 #[extendable]
 pub enum HostExtNotif {
-	SystemDrop(system::SystemDrop),
-	AtomDrop(atom::AtomDrop),
 	/// The host can assume that after this notif is sent, a correctly written
 	/// extension will eventually exit.
 	Exit,

orchid-api/src/system.rs

@@ -5,7 +5,7 @@ use orchid_api_derive::{Coding, Hierarchy};
 use orchid_api_traits::Request;
 use ordered_float::NotNan;
 
-use crate::{CharFilter, ExtHostReq, HostExtNotif, HostExtReq, MemberKind, TStr, TStrv};
+use crate::{CharFilter, ExtHostReq, HostExtReq, MemberKind, TStr, TStrv};
 
 /// ID of a system type
 #[derive(Copy, Clone, Debug, Hash, PartialEq, Eq, PartialOrd, Ord, Coding)]
@@ -67,8 +67,11 @@ pub struct NewSystemResponse {
 }
 
 #[derive(Clone, Debug, Coding, Hierarchy)]
-#[extends(HostExtNotif)]
+#[extends(HostExtReq)]
 pub struct SystemDrop(pub SysId);
+impl Request for SystemDrop {
+	type Response = ();
+}
 
 #[derive(Clone, Debug, Coding, Hierarchy)]
 #[extends(SysReq, HostExtReq)]