Most files suffered major changes

- Less ambiguous syntax
- Better parser (Chumsky only does tokenization now)
- Tidy(|ier) error handling
- Facade for simplified embedding
- External code grouped in (fairly) self-contained Systems
- Dynamic action dispatch
- Many STL additions

src/error/import_all.rs

@@ -0,0 +1,34 @@
+use std::rc::Rc;
+
+use super::{ErrorPosition, ProjectError};
+use crate::representations::location::Location;
+use crate::utils::iter::box_once;
+use crate::utils::BoxedIter;
+use crate::{Interner, VName};
+
+/// Error produced for the statement `import *`
+#[derive(Clone, Debug, PartialEq, Eq, Hash)]
+pub struct ImportAll {
+  /// The file containing the offending import
+  pub offender_file: Rc<Vec<String>>,
+  /// The module containing the offending import
+  pub offender_mod: Rc<VName>,
+}
+impl ProjectError for ImportAll {
+  fn description(&self) -> &str {
+    "a top-level glob import was used"
+  }
+  fn message(&self, i: &Interner) -> String {
+    format!("{} imports *", i.extern_all(&self.offender_mod).join("::"))
+  }
+
+  fn positions(&self, i: &Interner) -> BoxedIter<ErrorPosition> {
+    box_once(ErrorPosition {
+      location: Location::File(self.offender_file.clone()),
+      message: Some(format!(
+        "{} imports *",
+        i.extern_all(&self.offender_mod).join("::")
+      )),
+    })
+  }
+}