Oversight in Top/Bottom parsing.

tests/test_lang.py

@@ -194,9 +194,11 @@ def test_parse_type_uri(self):
         lang = Language(scope=locals(), namespace=EX, canon={F(F(A, A), A)})
         t = F(F(A, A), A)
         s = F(A, F(A, A))
+        u = F(A, F(Top, A))
         self.assertEqual(lang.uri(t), EX["F-F-A-A-A"])
         self.assertEqual(lang.parse_type_uri(EX["F-F-A-A-A"]), t)
         self.assertEqual(lang.parse_type_uri(EX["F-A-F-A-A"]), s)
+        self.assertEqual(lang.parse_type_uri(EX["F-A-F-Top-A"]), u)
 
 
 if __name__ == '__main__':

transforge/lang.py

@@ -11,7 +11,7 @@
 from rdflib.namespace import ClosedNamespace
 from collections import defaultdict
 
-from transforge.namespace import TF, EX
+from transforge.namespace import TF, EX, shorten
 from transforge.type import (builtins, Product, TypeOperator,
     TypeInstance, TypeVariable, TypeOperation, TypeAlias, Direction, Type,
     TypeSchema, TypingError, Top, Bottom)
@@ -340,7 +340,14 @@ def parse_operator(self, token: str) -> Operator:
     def parse_type_uri(self, uri: URIRef) -> TypeInstance:
         """Parse an URI back to a concrete type instance. Inverse operation to 
         `.uri()`."""
-        ops = [self.types[x] for x in uri[len(self.namespace):].split("-")]
+        ops = []
+        for x in shorten(uri).split("-"):
+            if x == "Top":
+                ops.append(Top)
+            elif x == "Bottom":
+                ops.append(Bottom)
+            else:
+                ops.append(self.types[x])
         types: list[TypeInstance] = []
         while ops:
             op = ops.pop()