feat(checker): add top type (Any)

midas/checker/builtins.py

@@ -5,6 +5,7 @@ from typing import TYPE_CHECKING
 from midas.checker.types import (
     BaseType,
     GenericType,
+    TopType,
     Type,
     TypeVar,
     UnitType,
@@ -40,6 +41,7 @@ def basic_op(reg: TypesRegistry, type: Type, op: str):
 
 def define_builtins(reg: TypesRegistry):
     """Define builtin types and operations"""
+    any = reg.define_type("Any", TopType())
     unit = reg.define_type("None", UnitType())
     object = reg.define_type("object", BaseType(name="object"))
     bool = reg.define_type("bool", BaseType(name="bool"))

midas/checker/registry.py

@@ -12,6 +12,7 @@ from midas.checker.types import (
     GenericType,
     Operation,
     OverloadedFunction,
+    TopType,
     Type,
     TypeVar,
     UnknownType,
@@ -155,6 +156,9 @@ class TypesRegistry:
             return True
 
         match (type1, type2):
+            case (_, TopType()):
+                return True
+
             case (AliasType(type=base1), _):
                 return self.is_subtype(base1, type2)
 

midas/checker/types.py

@@ -4,6 +4,12 @@ from dataclasses import dataclass
 from typing import Optional
 
 
+@dataclass(frozen=True, kw_only=True)
+class TopType:
+    def __str__(self) -> str:
+        return "Any"
+
+
 @dataclass(frozen=True, kw_only=True)
 class BaseType:
     name: str
@@ -222,7 +228,8 @@ def unfold_type(type: Type) -> Type:
 
 
 Type = (
-    BaseType
+    TopType
+    | BaseType
     | AliasType
     | UnknownType
     | UnitType