Added support for defining macros in Rust within the macro system

Also fixed a lot of bugs

orchid-std/src/macros/instantiate_tpl.rs

@@ -1,9 +1,11 @@
 use std::borrow::Cow;
 
 use never::Never;
-use orchid_extension::atom::{Atomic, TypAtom};
+use orchid_base::format::fmt;
+use orchid_extension::atom::{Atomic, TAtom};
 use orchid_extension::atom_owned::{OwnedAtom, OwnedVariant, own};
-use orchid_extension::conv::{ToExpr, TryFromExpr};
+use orchid_extension::conv::ToExpr;
+use orchid_extension::coroutine_exec::exec;
 use orchid_extension::expr::Expr;
 use orchid_extension::gen_expr::GExpr;
 
@@ -24,26 +26,33 @@ impl OwnedAtom for InstantiateTplCall {
 	type Refs = Never;
 	// Technically must be supported but shouldn't actually ever be called
 	async fn call_ref(&self, arg: Expr) -> GExpr {
-		eprintln!(
-			"Copying partially applied instantiate_tpl call. This is an internal value.\
-      \nIt should be fully consumed within generated code."
-		);
+		if !self.argv.is_empty() {
+			eprintln!(
+				"Copying partially applied instantiate_tpl call. This is an internal value.\
+				\nIt should be fully consumed within generated code."
+			);
+		}
 		self.clone().call(arg).await
 	}
 	async fn call(mut self, arg: Expr) -> GExpr {
-		match TypAtom::<MacTree>::try_from_expr(arg).await {
-			Err(e) => return Err::<Never, _>(e).to_expr().await,
-			Ok(t) => self.argv.push(own(t).await),
-		};
-		if self.argv.len() < self.argc {
-			return self.to_expr().await;
-		}
-		let mut args = self.argv.into_iter();
-		let ret = map_mactree(&self.tpl, &mut false, &mut |mt| match mt.tok() {
-			MacTok::Slot => Some(args.next().expect("Not enough arguments to fill all slots")),
-			_ => None,
-		});
-		assert!(args.next().is_none(), "Too many arguments for all slots");
-		ret.to_expr().await
+		exec("macros::instantiate_tpl", async move |mut h| {
+			match h.exec::<TAtom<MacTree>>(arg.clone()).await {
+				Err(_) => panic!("Expected a macro param, found {}", fmt(&arg, arg.ctx().i()).await),
+				Ok(t) => self.argv.push(own(t).await),
+			};
+			if self.argv.len() < self.argc {
+				return self.to_expr().await;
+			}
+			let mut args = self.argv.into_iter();
+			let ret = map_mactree(&self.tpl, &mut false, &mut |mt| match mt.tok() {
+				MacTok::Slot => Some(args.next().expect("Not enough arguments to fill all slots")),
+				_ => None,
+			});
+			assert!(args.next().is_none(), "Too many arguments for all slots");
+			ret.to_expr().await
+		})
+		.await
+		.to_expr()
+		.await
 	}
 }