Import and export improved

- Import paths are now vname and not sym
- Imports and exports accept multiple space-delimited operators in []

as a result, we can now reliably import and export the operator *

- error reporting ergonomics

src/systems/stl/prelude.orc

@@ -1,11 +1,11 @@
 import std::num::*
-export ::(+, -, *, /, %)
+export ::[+ - * / %]
 import std::str::*
 export ::[++]
 import std::bool::*
-export ::(==, if, then, else, true, false)
+export ::([==], if, then, else, true, false)
 import std::fn::*
-export ::($, |>, =>, identity, pass, pass2, return)
+export ::([$ |> =>], identity, pass, pass2, return)
 import std::list
 import std::map
 import std::option

src/systems/stl/stl_system.rs

@@ -41,7 +41,7 @@ impl IntoSystem<'static> for StlConfig {
       constants: HashMap::from([(i.i("std"), fns)]),
       code: embed_to_map::<StlEmbed>(".orc", i),
       prelude: vec![FileEntry::Import(vec![Import {
-        path: i.i(&[i.i("std"), i.i("prelude")][..]),
+        path: vec![i.i("std"), i.i("prelude")],
         name: None,
       }])],
       handlers: HandlerTable::new(),