nac3core: option type front end

nac3core/src/codegen/mod.rs

@@ -385,6 +385,7 @@ pub fn gen_func<'ctx, G: CodeGenerator>(
         range: unifier.get_representative(primitives.range),
         str: unifier.get_representative(primitives.str),
         exception: unifier.get_representative(primitives.exception),
+        option: unifier.get_representative(primitives.option),
     };
 
     let mut type_cache: HashMap<_, _> = [
@@ -417,6 +418,7 @@ pub fn gen_func<'ctx, G: CodeGenerator>(
         exception.set_body(&fields, false);
         exception.ptr_type(AddressSpace::Generic).into()
     });
+    // TODO: insert option type cache
 
     let (args, ret) = if let ConcreteTypeEnum::TFunc { args, ret, .. } =
         task.store.get(task.signature)

nac3core/src/toplevel/builtins.rs

@@ -105,6 +105,20 @@ pub fn get_builtins(primitives: &mut (PrimitiveStore, Unifier)) -> BuiltinInfo {
         ("__param2__".into(), int64, true),
     ];
 
+    // for Option, is_some and is_none share the same type: () -> bool,
+    // and they are methods under the same class `Option`
+    let (is_some_ty, unwrap_ty, (option_ty_var, option_ty_var_id)) =
+        if let TypeEnum::TObj { fields, params, .. } =
+            primitives.1.get_ty(primitives.0.option).as_ref()
+        {
+            (
+                *fields.get(&"is_some".into()).unwrap(),
+                *fields.get(&"unwrap".into()).unwrap(),
+                (*params.iter().next().unwrap().1, *params.iter().next().unwrap().0),
+            )
+        } else {
+            unreachable!()
+        };
     let top_level_def_list = vec![
         Arc::new(RwLock::new(TopLevelComposer::make_top_level_class_def(
             0,
@@ -180,6 +194,58 @@ pub fn get_builtins(primitives: &mut (PrimitiveStore, Unifier)) -> BuiltinInfo {
             None,
             None,
         ))),
+        Arc::new(RwLock::new({
+            TopLevelDef::Class {
+                name: "Option".into(),
+                object_id: DefinitionId(10),
+                type_vars: vec![option_ty_var],
+                fields: vec![],
+                methods: vec![
+                    ("is_some".into(), is_some_ty.0, DefinitionId(11)),
+                    ("is_none".into(), is_some_ty.0, DefinitionId(12)),
+                    ("unwrap".into(), unwrap_ty.0, DefinitionId(13)),
+                ],
+                ancestors: vec![TypeAnnotation::CustomClass {
+                    id: DefinitionId(10),
+                    params: Default::default(),
+                }],
+                constructor: None,
+                resolver: None,
+                loc: None,
+            }
+        })),
+        Arc::new(RwLock::new(TopLevelDef::Function {
+            name: "Option.is_some".into(),
+            simple_name: "is_some".into(),
+            signature: is_some_ty.0,
+            var_id: vec![option_ty_var_id],
+            instance_to_symbol: Default::default(),
+            instance_to_stmt: Default::default(),
+            resolver: None,
+            codegen_callback: Some(Arc::new(GenCall::new(Box::new(
+                |ctx, _, fun, args, generator| {
+                    // TODO:
+                    unimplemented!()
+                },
+            )))),
+            loc: None,
+        })),
+        Arc::new(RwLock::new(TopLevelDef::Function {
+            name: "Option.unwrap".into(),
+            simple_name: "unwrap".into(),
+            signature: unwrap_ty.0,
+            var_id: vec![option_ty_var_id],
+            instance_to_symbol: Default::default(),
+            instance_to_stmt: Default::default(),
+            resolver: None,
+            codegen_callback: Some(Arc::new(GenCall::new(Box::new(
+                |ctx, _, fun, args, generator| {
+                    // TODO:
+                    unimplemented!()
+                },
+            )))),
+            loc: None,
+        })),
         Arc::new(RwLock::new(TopLevelDef::Function {
             name: "int32".into(),
             simple_name: "int32".into(),
@@ -1098,6 +1164,25 @@ pub fn get_builtins(primitives: &mut (PrimitiveStore, Unifier)) -> BuiltinInfo {
             )))),
             loc: None,
         })),
+        Arc::new(RwLock::new(TopLevelDef::Function {
+            name: "Some".into(),
+            simple_name: "Some".into(),
+            signature: primitives.1.add_ty(TypeEnum::TFunc(FunSignature {
+                args: vec![FuncArg { name: "n".into(), ty: option_ty_var, default_value: None }],
+                ret: primitives.0.option,
+                vars: HashMap::from([(option_ty_var_id, option_ty_var)]),
+            })),
+            var_id: vec![option_ty_var_id],
+            instance_to_symbol: Default::default(),
+            instance_to_stmt: Default::default(),
+            resolver: None,
+            codegen_callback: Some(Arc::new(GenCall::new(Box::new(
+                |ctx, _, fun, args, generator| {
+                    unimplemented!()
+                },
+            )))),
+            loc: None,
+        })),
     ];
 
     let ast_list: Vec<Option<ast::Stmt<()>>> =
@@ -1123,6 +1208,7 @@ pub fn get_builtins(primitives: &mut (PrimitiveStore, Unifier)) -> BuiltinInfo {
             "min",
             "max",
             "abs",
+            "Some",
         ],
     )
 }

nac3core/src/toplevel/composer.rs

@@ -74,6 +74,8 @@ impl TopLevelComposer {
             "self".into(),
             "Kernel".into(),
             "KernelInvariant".into(),
+            "Some".into(),
+            "Option".into(),
         ]);
         let defined_names: HashSet<String> = Default::default();
         let method_class: HashMap<DefinitionId, DefinitionId> = Default::default();
@@ -92,7 +94,6 @@ impl TopLevelComposer {
             } else if let TopLevelDef::Class { name, constructor, object_id, type_vars, .. } = &*def
             {
                 assert!(id == object_id.0);
-                assert!(type_vars.is_empty());
                 if let Some(constructor) = constructor {
                     builtin_ty.insert(*name, *constructor);
                 }

nac3core/src/toplevel/helper.rs

@@ -107,7 +107,42 @@ impl TopLevelComposer {
             fields: HashMap::new(),
             params: HashMap::new(),
         });
-        let primitives = PrimitiveStore { int32, int64, float, bool, none, range, str, exception, uint32, uint64 };
+
+        let option_type_var = unifier.get_fresh_var(Some("option_type_var".into()), None);
+        let is_some_type_fun_ty = unifier.add_ty(TypeEnum::TFunc(FunSignature {
+            args: vec![],
+            ret: bool,
+            vars: HashMap::from([(option_type_var.1, option_type_var.0)]),
+        }));
+        let unwrap_fun_ty = unifier.add_ty(TypeEnum::TFunc(FunSignature {
+            args: vec![],
+            ret: option_type_var.0,
+            vars: HashMap::from([(option_type_var.1, option_type_var.0)]),
+        }));
+        let option = unifier.add_ty(TypeEnum::TObj {
+            obj_id: DefinitionId(10),
+            fields: vec![
+                ("is_some".into(), (is_some_type_fun_ty, true)),
+                ("unwrap".into(), (unwrap_fun_ty, true)),
+            ]
+            .into_iter()
+            .collect::<HashMap<_, _>>(),
+            params: HashMap::from([(option_type_var.1, option_type_var.0)]),
+        });
+
+        let primitives = PrimitiveStore {
+            int32,
+            int64,
+            float,
+            bool,
+            none,
+            range,
+            str,
+            exception,
+            uint32,
+            uint64,
+            option,
+        };
         crate::typecheck::magic_methods::set_primitives_magic_methods(&primitives, &mut unifier);
         (primitives, unifier)
     }

nac3core/src/toplevel/type_annotation.rs

@@ -223,6 +223,29 @@ pub fn parse_ast_to_type_annotation_kinds<T>(
             Ok(TypeAnnotation::List(def_ann.into()))
         }
 
+        // option
+        ast::ExprKind::Subscript { value, slice, .. }
+            if {
+                matches!(&value.node, ast::ExprKind::Name { id, .. } if id == &"Option".into())
+            } =>
+        {
+            let def_ann = parse_ast_to_type_annotation_kinds(
+                resolver,
+                top_level_defs,
+                unifier,
+                primitives,
+                slice.as_ref(),
+                locked,
+            )?;
+            let id =
+                if let TypeEnum::TObj { obj_id, .. } = unifier.get_ty(primitives.option).as_ref() {
+                    *obj_id
+                } else {
+                    unreachable!()
+                };
+            Ok(TypeAnnotation::CustomClass { id, params: vec![def_ann] })
+        }
+
         // tuple
         ast::ExprKind::Subscript { value, slice, .. }
             if {

nac3core/src/typecheck/type_inferencer/mod.rs

@@ -40,6 +40,7 @@ pub struct PrimitiveStore {
     pub range: Type,
     pub str: Type,
     pub exception: Type,
+    pub option: Type,
 }
 
 pub struct FunctionData {
@@ -932,6 +933,17 @@ impl<'a> Inferencer<'a> {
                 Ok(self.unifier.add_ty(TypeEnum::TTuple { ty: ty? }))
             }
             ast::Constant::Str(_) => Ok(self.primitives.str),
+            ast::Constant::None => {
+                let option_ty = self.primitives.option;
+                let new_mapping = if let TypeEnum::TObj { params, .. } = &*self.unifier.get_ty_immutable(option_ty) {
+                    let (id, _) = params.iter().next().unwrap();
+                    // None can be Option[Any]
+                    vec![(*id, self.unifier.get_fresh_var(None, None).0)].into_iter().collect()
+                } else {
+                    unreachable!("option must be tobj")
+                };
+                Ok(self.unifier.subst(option_ty, &new_mapping).unwrap())
+            }
             _ => report_error("not supported", *loc),
         }
     }