nullable: convert lib, tools and tests

[nit.git] / src / metamodel / type_formal.nit

diff --git a/src/metamodel/type_formal.nit b/src/metamodel/type_formal.nit
index fcbcb87..5ecf49f 100644 (file)
--- a/src/metamodel/type_formal.nit
+++ b/src/metamodel/type_formal.nit
@@ -28,27 +28,24 @@ end
 # Formal types are named indirect types
 class MMTypeFormal
 special MMType
-       redef meth is_valid do return _bound != null
+       redef meth is_valid do return _bound != null and _bound.is_valid
 
        # The name of the type
-       readable attr _name: Symbol 
+       readable attr _name: Symbol
 
        # The type refered
-       meth bound: MMType
-       do
-               assert is_valid
-               return _bound
-       end
-       attr _bound: MMType
+       meth bound: MMType do return _bound.as(not null)
+       attr _bound: nullable MMType
 
-       redef meth <(t) do return t != null and (t == self or t.is_supertype(_bound))
+       redef meth <(t) do return t == self or t.is_supertype(bound)
        redef meth is_supertype(t) do return _bound.is_supertype(t)
+       redef meth is_nullable do return _bound.is_nullable
        redef meth direct_type do return _bound.direct_type
        redef meth local_class do return _bound.local_class
 
        redef meth to_s do return _name.to_s
 
-       protected init(name: Symbol, bound: MMType)
+       protected init(name: Symbol, bound: nullable MMType)
        do
                _name = name
                _bound = bound