Added support for defining macros in Rust within the macro system

Also fixed a lot of bugs

orchid-std/src/macros/mactree.rs

@@ -6,6 +6,7 @@ use futures::FutureExt;
 use futures::future::join_all;
 use hashbrown::HashSet;
 use itertools::Itertools;
+use orchid_api_derive::Coding;
 use orchid_base::error::{OrcErrv, Reporter, mk_errv};
 use orchid_base::format::{FmtCtx, FmtUnit, Format, Variants, fmt};
 use orchid_base::interner::Tok;
@@ -42,38 +43,56 @@ impl MacTree {
 			MacTok::Bottom(e) => bot(e.clone()),
 			MacTok::Lambda(arg, body) => {
 				let MacTok::Name(name) = &*arg.tok else {
-					let err = mk_errv(
+					return bot(mk_errv(
 						ctx.sys.i().i("Syntax error after macros").await,
 						"This token ends up as a binding, consider replacing it with a name",
 						[arg.pos()],
-					);
-					ctx.rep.report(err.clone());
-					return bot(err);
+					));
 				};
-				lambda(args.len() as u64, lower_v(body, ctx, args.push(name.clone())).await)
+				let arg_pos = args.len() as u64;
+				let args = args.push(name.clone());
+				let body = match &body[..] {
+					[] => bot(mk_errv(
+						ctx.sys.i().i("Empty lambda body").await,
+						"Lambdas must evaluate to an expression",
+						[self.pos()],
+					)),
+					[f, argv @ ..] => call(
+						f.lower(ctx.clone(), args.clone()).boxed_local().await,
+						lower_v(argv, ctx, args).await,
+					),
+				};
+				lambda(arg_pos, body)
 			},
 			MacTok::Name(name) => match args.iter().enumerate().find(|(_, n)| *n == name) {
 				None => sym_ref(name.clone()),
-				Some((i, _)) => arg((args.len() - i) as u64),
+				Some((i, _)) => arg((args.len() - i - 1) as u64),
 			},
 			MacTok::Ph(ph) => {
-				let err = mk_errv(
+				return bot(mk_errv(
 					ctx.sys.i().i("Placeholder in value").await,
 					format!("Placeholder {ph} is only supported in macro patterns"),
 					[self.pos()],
-				);
-				ctx.rep.report(err.clone());
-				return bot(err);
+				));
+			},
+			MacTok::S(Paren::Round, body) => match &body[..] {
+				[fun, argv @ ..] => call(
+					fun.lower(ctx.clone(), args.clone()).boxed_local().await,
+					lower_v(argv, ctx, args).await,
+				),
+				[] =>
+					return bot(mk_errv(
+						ctx.sys.i().i("Empty ()").await,
+						"Empty () is not a meaningful expression",
+						[self.pos()],
+					)),
 			},
-			MacTok::S(Paren::Round, body) => call(lower_v(body, ctx, args).await),
 			MacTok::S(..) => {
-				let err = mk_errv(
+				return bot(mk_errv(
 					ctx.sys.i().i("[] or {} after macros").await,
 					format!("{} didn't match any macro", fmt(self, ctx.sys.i()).await),
 					[self.pos()],
-				);
-				ctx.rep.report(err.clone());
-				return bot(err);
+				));
 			},
 			MacTok::Slot => panic!("Uninstantiated template should never be exposed"),
 			MacTok::Value(v) => v.clone().to_expr().await,
@@ -90,7 +109,8 @@ impl OwnedAtom for MacTree {
 
 	async fn val(&self) -> Cow<'_, Self::Data> { Cow::Owned(()) }
 	async fn print_atom<'a>(&'a self, c: &'a (impl FmtCtx + ?Sized + 'a)) -> FmtUnit {
-		self.tok.print(c).await
+		tl_cache!(Rc<Variants>: Rc::new(Variants::default().bounded("'{0}")))
+			.units([self.tok.print(c).await])
 	}
 }
 impl Format for MacTree {
@@ -134,22 +154,18 @@ impl Format for MacTok {
 	async fn print<'a>(&'a self, c: &'a (impl FmtCtx + ?Sized + 'a)) -> FmtUnit {
 		match self {
 			Self::Value(v) => v.print(c).await,
-			Self::Lambda(arg, b) => FmtUnit::new(
-				tl_cache!(Rc<Variants>: Rc::new(Variants::default()
-					.unbounded("\\{0b}.{1l}")
-					.bounded("(\\{0b}.{1b})"))),
-				[arg.print(c).boxed_local().await, mtreev_fmt(b, c).await],
-			),
+			Self::Lambda(arg, b) => tl_cache!(Rc<Variants>: Rc::new(Variants::default()
+					.unbounded("\\{0} {1l}")
+					.bounded("(\\{0} {1b})")))
+			.units([arg.print(c).boxed_local().await, mtreev_fmt(b, c).await]),
 			Self::Name(n) => format!("{n}").into(),
 			Self::Ph(ph) => format!("{ph}").into(),
-			Self::S(p, body) => FmtUnit::new(
-				match *p {
-					Paren::Round => Rc::new(Variants::default().bounded("({0b})")),
-					Paren::Curly => Rc::new(Variants::default().bounded("{{0b}}")),
-					Paren::Square => Rc::new(Variants::default().bounded("[{0b}]")),
-				},
-				[mtreev_fmt(body, c).await],
-			),
+			Self::S(p, body) => match *p {
+				Paren::Round => tl_cache!(Rc<Variants>: Rc::new(Variants::default().bounded("({0b})"))),
+				Paren::Curly => tl_cache!(Rc<Variants>: Rc::new(Variants::default().bounded("{{0b}}"))),
+				Paren::Square => tl_cache!(Rc<Variants>: Rc::new(Variants::default().bounded("[{0b}]"))),
+			}
+			.units([mtreev_fmt(body, c).await]),
 			Self::Slot => "$SLOT".into(),
 			Self::Bottom(err) if err.len() == 1 => format!("Bottom({}) ", err.one().unwrap()).into(),
 			Self::Bottom(err) => format!("Botttom(\n{}) ", indent(&err.to_string())).into(),
@@ -181,7 +197,7 @@ impl Display for Ph {
 	}
 }
 
-#[derive(Copy, Clone, Debug, Hash, PartialEq, Eq)]
+#[derive(Copy, Clone, Debug, Hash, PartialEq, Eq, Coding)]
 pub enum PhKind {
 	Scalar,
 	Vector { at_least_one: bool, priority: u8 },