core: Codegen for ellipsis expression

nac3core/src/codegen/expr.rs

@@ -207,12 +207,12 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
         generator: &mut dyn CodeGenerator,
         value: &Constant,
         ty: Type,
-    ) -> BasicValueEnum<'ctx> {
+    ) -> Option<BasicValueEnum<'ctx>> {
         match value {
             Constant::Bool(v) => {
                 assert!(self.unifier.unioned(ty, self.primitives.bool));
                 let ty = self.ctx.i8_type();
-                ty.const_int(if *v { 1 } else { 0 }, false).into()
+                Some(ty.const_int(if *v { 1 } else { 0 }, false).into())
             }
             Constant::Int(val) => {
                 let ty = if self.unifier.unioned(ty, self.primitives.int32)
@@ -226,28 +226,33 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
                 } else {
                     unreachable!();
                 };
-                ty.const_int(*val as u64, false).into()
+                Some(ty.const_int(*val as u64, false).into())
             }
             Constant::Float(v) => {
                 assert!(self.unifier.unioned(ty, self.primitives.float));
                 let ty = self.ctx.f64_type();
-                ty.const_float(*v).into()
+                Some(ty.const_float(*v).into())
             }
             Constant::Tuple(v) => {
                 let ty = self.unifier.get_ty(ty);
                 let types =
                     if let TypeEnum::TTuple { ty } = &*ty { ty.clone() } else { unreachable!() };
                 let values = zip(types.into_iter(), v.iter())
-                    .map(|(ty, v)| self.gen_const(generator, v, ty))
+                    .map_while(|(ty, v)| self.gen_const(generator, v, ty))
                     .collect_vec();
-                let types = values.iter().map(BasicValueEnum::get_type).collect_vec();
-                let ty = self.ctx.struct_type(&types, false);
-                ty.const_named_struct(&values).into()
+
+                if values.len() == v.len() {
+                    let types = values.iter().map(BasicValueEnum::get_type).collect_vec();
+                    let ty = self.ctx.struct_type(&types, false);
+                    Some(ty.const_named_struct(&values).into())
+                } else {
+                    None
+                }
             }
             Constant::Str(v) => {
                 assert!(self.unifier.unioned(ty, self.primitives.str));
                 if let Some(v) = self.const_strings.get(v) {
-                    *v
+                    Some(*v)
                 } else {
                     let str_ptr =
                         self.builder.build_global_string_ptr(v, "const").as_pointer_value().into();
@@ -256,9 +261,22 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
                     let val =
                         ty.into_struct_type().const_named_struct(&[str_ptr, size.into()]).into();
                     self.const_strings.insert(v.to_string(), val);
-                    val
+                    Some(val)
                 }
             }
+            Constant::Ellipsis => {
+                let msg = self.gen_string(generator, "");
+
+                self.raise_exn(
+                    generator,
+                    "0:NotImplementedError",
+                    msg,
+                    [None, None, None],
+                    self.current_loc,
+                );
+
+                None
+            }
             _ => unreachable!(),
         }
     }
@@ -481,7 +499,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
         generator: &mut dyn CodeGenerator,
         s: S,
     ) -> BasicValueEnum<'ctx> {
-        self.gen_const(generator, &nac3parser::ast::Constant::Str(s.into()), self.primitives.str)
+        self.gen_const(generator, &nac3parser::ast::Constant::Str(s.into()), self.primitives.str).unwrap()
     }
 
     pub fn raise_exn(
@@ -1211,7 +1229,10 @@ pub fn gen_expr<'ctx, 'a, G: CodeGenerator>(
     Ok(Some(match &expr.node {
         ExprKind::Constant { value, .. } => {
             let ty = expr.custom.unwrap();
-            ctx.gen_const(generator, value, ty).into()
+            let Some(const_val) = ctx.gen_const(generator, value, ty) else {
+                return Ok(None)
+            };
+            const_val.into()
         }
         ExprKind::Name { id, .. } if id == &"none".into() => {
             match (

nac3core/src/codegen/stmt.rs

@@ -604,7 +604,7 @@ pub fn exn_constructor<'ctx, 'a>(
         let msg = if !args.is_empty() {
             args.remove(0).1.to_basic_value_enum(ctx, generator, ctx.primitives.str)?
         } else {
-            empty_string
+            empty_string.unwrap()
         };
         ctx.builder.build_store(ptr, msg);
         for i in [6, 7, 8].iter() {
@@ -627,7 +627,7 @@ pub fn exn_constructor<'ctx, 'a>(
                 &[zero, int32.const_int(*i, false)],
                 "exn.str",
             );
-            ctx.builder.build_store(ptr, empty_string);
+            ctx.builder.build_store(ptr, empty_string.unwrap());
         }
         // set ints to zero
         for i in [2, 3].iter() {

nac3core/src/typecheck/function_check.rs

@@ -62,7 +62,7 @@ impl<'a> Inferencer<'a> {
     ) -> Result<(), String> {
         // there are some cases where the custom field is None
         if let Some(ty) = &expr.custom {
-            if !self.unifier.is_concrete(*ty, &self.function_data.bound_variables) {
+            if !matches!(&expr.node, ExprKind::Constant { value: Constant::Ellipsis, .. }) && !self.unifier.is_concrete(*ty, &self.function_data.bound_variables) {
                 return Err(format!(
                     "expected concrete type at {} but got {}",
                     expr.location,

nac3core/src/typecheck/type_inferencer/mod.rs

@@ -964,6 +964,7 @@ impl<'a> Inferencer<'a> {
             ast::Constant::Str(_) => Ok(self.primitives.str),
             ast::Constant::None
                 => report_error("CPython `None` not supported (nac3 uses `none` instead)", *loc),
+            ast::Constant::Ellipsis => Ok(self.unifier.get_fresh_var(None, None).0),
             _ => report_error("not supported", *loc),
         }
     }