use std::cell::RefCell; use std::collections::HashMap; use crate::top_level::{DefinitionId, TopLevelContext, TopLevelDef}; use crate::typecheck::{ type_inferencer::PrimitiveStore, typedef::{Type, Unifier}, }; use crate::{location::Location, typecheck::typedef::TypeEnum}; use itertools::{chain, izip}; use rustpython_parser::ast::Expr; #[derive(Clone, PartialEq)] pub enum SymbolValue { I32(i32), I64(i64), Double(f64), Bool(bool), Tuple(Vec), // we should think about how to implement bytes later... // Bytes(&'a [u8]), } pub trait SymbolResolver { // get type of type variable identifier or top-level function type fn get_symbol_type( &self, unifier: &mut Unifier, primitives: &PrimitiveStore, str: &str, ) -> Option; // get the top-level definition of identifiers fn get_identifier_def(&self, str: &str) -> Option; fn get_symbol_value(&self, str: &str) -> Option; fn get_symbol_location(&self, str: &str) -> Option; // handle function call etc. } impl dyn SymbolResolver { // convert type annotation into type pub fn parse_type_annotation( &self, top_level: &TopLevelContext, unifier: &mut Unifier, primitives: &PrimitiveStore, expr: &Expr, ) -> Result { use rustpython_parser::ast::ExprKind::*; match &expr.node { Name { id, .. } => match id.as_str() { "int32" => Ok(primitives.int32), "int64" => Ok(primitives.int64), "float" => Ok(primitives.float), "bool" => Ok(primitives.bool), "None" => Ok(primitives.none), x => { let obj_id = self.get_identifier_def(x); if let Some(obj_id) = obj_id { let defs = top_level.definitions.read(); let def = defs[obj_id.0].read(); if let TopLevelDef::Class { fields, methods, type_vars, .. } = &*def { if !type_vars.is_empty() { return Err(format!( "Unexpected number of type parameters: expected {} but got 0", type_vars.len() )); } let fields = RefCell::new( chain( fields.iter().map(|(k, v)| (k.clone(), *v)), methods.iter().map(|(k, v, _)| (k.clone(), *v)), ) .collect(), ); Ok(unifier.add_ty(TypeEnum::TObj { obj_id, fields, params: Default::default(), })) } else { Err("Cannot use function name as type".into()) } } else { // it could be a type variable let ty = self .get_symbol_type(unifier, primitives, x) .ok_or_else(|| "Cannot use function name as type".to_owned())?; if let TypeEnum::TVar { .. } = &*unifier.get_ty(ty) { Ok(ty) } else { Err(format!("Unknown type annotation {}", x)) } } } }, Subscript { value, slice, .. } => { if let Name { id, .. } = &value.node { if id == "virtual" { let ty = self.parse_type_annotation(top_level, unifier, primitives, slice)?; Ok(unifier.add_ty(TypeEnum::TVirtual { ty })) } else { let types = if let Tuple { elts, .. } = &slice.node { elts.iter() .map(|v| { self.parse_type_annotation(top_level, unifier, primitives, v) }) .collect::, _>>()? } else { vec![self.parse_type_annotation(top_level, unifier, primitives, slice)?] }; let obj_id = self .get_identifier_def(id) .ok_or_else(|| format!("Unknown type annotation {}", id))?; let defs = top_level.definitions.read(); let def = defs[obj_id.0].read(); if let TopLevelDef::Class { fields, methods, type_vars, .. } = &*def { if types.len() != type_vars.len() { return Err(format!( "Unexpected number of type parameters: expected {} but got {}", type_vars.len(), types.len() )); } let mut subst = HashMap::new(); for (var, ty) in izip!(type_vars.iter(), types.iter()) { let id = if let TypeEnum::TVar { id, .. } = &*unifier.get_ty(*var) { *id } else { unreachable!() }; subst.insert(id, *ty); } let mut fields = fields .iter() .map(|(attr, ty)| { let ty = unifier.subst(*ty, &subst).unwrap_or(*ty); (attr.clone(), ty) }) .collect::>(); fields.extend(methods.iter().map(|(attr, ty, _)| { let ty = unifier.subst(*ty, &subst).unwrap_or(*ty); (attr.clone(), ty) })); Ok(unifier.add_ty(TypeEnum::TObj { obj_id, fields: fields.into(), params: subst.into() })) } else { Err("Cannot use function name as type".into()) } } } else { Err("unsupported type expression".into()) } } _ => Err("unsupported type expression".into()), } } }