[fine] Lookup semantics by mid

This isn't actually correct, I really need a global view to make this
right.

fine/src/semantics.rs

@@ -664,6 +664,12 @@ enum Incremental<T> {
     Complete(T),
 }
 
+#[derive(Debug)]
+struct ImportMap {
+    by_name: HashMap<String, ImportRecord>,
+    by_id: HashMap<ModuleId, ImportRecord>,
+}
+
 pub struct Semantics {
     mid: ModuleId,
     file: Rc<str>,
@@ -671,7 +677,7 @@ pub struct Semantics {
     syntax_tree: Rc<SyntaxTree>,
     lines: Rc<Lines>,
 
-    import_map: OnceCell<HashMap<String, ImportRecord>>,
+    import_map: OnceCell<ImportMap>,
 
     // Instead of physical parents, this is the set of *logical* parents.
     // This is what is used for binding.
@@ -726,9 +732,26 @@ impl Semantics {
     }
 
     pub fn set_imports(&self, imports: HashMap<String, ImportRecord>) {
+        let mut by_id = HashMap::new();
+        for (_, v) in imports.iter() {
+            by_id.insert(v.module_id, v.clone());
+        }
+        let imports = ImportMap {
+            by_name: imports,
+            by_id,
+        };
+
         self.import_map.set(imports).expect("imports already set");
     }
 
+    pub fn import_by_id(&self, mid: ModuleId) -> Option<Rc<Semantics>> {
+        // TODO: ACTUALLY THIS IS WRONG, WE NEED THE GLOBAL MAP HERE, NOT THE LOCAL ONE.
+        let import_map = self.import_map.get()?;
+        let record = import_map.by_id.get(&mid)?;
+
+        record.semantics.upgrade()
+    }
+
     pub fn source(&self) -> Rc<str> {
         self.source.clone()
     }
@@ -1268,18 +1291,9 @@ impl Semantics {
 
     pub fn class_of(&self, mid: ModuleId, t: TreeRef) -> ClassRef {
         if mid != self.mid {
-            let weak_semantics = self
+            let Some(other_semantics) = self.import_by_id(mid) else {
-                .import_map
+                self.internal_compiler_error(Some(t), "Have a class we can't resolve");
-                .get()
+            };
-                .unwrap()
-                .iter()
-                .find(|(_, v)| v.module_id == mid)
-                .unwrap()
-                .1
-                .semantics
-                .clone();
-
-            let other_semantics = weak_semantics.upgrade().unwrap();
             return other_semantics.class_of(mid, t);
         }
 
@@ -2215,7 +2229,15 @@ impl Semantics {
                 if declaration.module == self.mid {
                     self.type_of(*t)
                 } else {
-                    self.internal_compiler_error(Some(*t), "Not implemented: deref this module");
+                    let Some(other_semantics) = self.import_by_id(declaration.module) else {
+                        let message = format!(
+                            "Cannot find a module matching this decl's mid: {:?}",
+                            declaration.module
+                        );
+                        self.internal_compiler_error(Some(*t), &message);
+                    };
+
+                    other_semantics.type_of(*t)
                 }
             }
         }
@@ -2364,6 +2386,26 @@ impl Semantics {
         // The details of a class are computed lazily, but this is enough of
         // a belly-button.
         let name = tree.nth_token(1)?;
+
+        // NOTE: There's a kind of a weird design decision here, which is to
+        //       return an instance type instead of a class type. This is
+        //       because it turns out to be what you want most of the time:
+        //       variables should be object type, arguments should be object
+        //       type, etc.
+        //
+        //       There are only two places where you have to deal with this
+        //       being weird: first, in the new object expression, and
+        //       second, in static member access.
+        //
+        //       For new object expression it turns out to not matter much,
+        //       you just have to be aware that the type identifier is an
+        //       object type.
+        //
+        //       For the static member access, that one is just plain weird.
+        //       But it's easier to handle converting object type -> class
+        //       type there (in type_of_identifier) rather than flipping the
+        //       default here and dealing with converting class type ->
+        //       object type literally everywhere else.
         Some(Type::Object(self.mid, t, name.as_str(&self.source).into()))
     }
 
@@ -2499,12 +2541,12 @@ impl Semantics {
         }
 
         // do we bind it here? it's not normalized....
+        let name = string_constant_to_string(tok.as_str(&self.source));
         let Some(import_map) = self.import_map.get() else {
             self.internal_compiler_error(None, "import map not initialized");
         };
 
-        let name = string_constant_to_string(tok.as_str(&self.source));
+        match import_map.by_name.get(&name) {
-        match import_map.get(&name) {
             Some(import) => Some(Type::Module(name.into(), import.clone())),
             None => {
                 let error =
@@ -2669,7 +2711,7 @@ impl Semantics {
             match self.import_map.get() {
                 Some(m) => {
                     eprintln!("Import map:");
-                    for (k, b) in m.iter() {
+                    for (k, b) in m.by_name.iter() {
                         eprintln!("  {k} => {} ({:?})", b.name, b.module_id);
                     }
                     eprintln!();

fine/tests/modules/import.fine

@@ -4,6 +4,5 @@ fun test() -> string {
   foo.hello() + " world"
 }
 
-// @ignore working on declaration rebuild
 // TODO: Obviously run the code duh
 // @no-errors