mm: implements metamodel for basic explicit casts

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

diff --git a/src/metamodel/static_type.nit b/src/metamodel/static_type.nit
index 65e70b9..4d443ce 100644 (file)
--- a/src/metamodel/static_type.nit
+++ b/src/metamodel/static_type.nit
@@ -540,3 +540,37 @@ redef class MMModule
                return class_by_name(once ("Bool".to_symbol)).get_type
        end
 end
+
+# Explicitly imported cast
+class MMImportedCast
+       readable var _from : MMType
+       readable var _to : MMType
+
+       fun is_about_nullable_only : Bool
+       do
+           return ( _from.is_nullable and _to.as_nullable == _from ) or
+                  ( _to.is_nullable and _from.as_nullable == _to )
+       end
+
+       fun is_not_null_to_nullable : Bool
+       do
+           return not _from.is_nullable and _to.is_nullable
+       end
+
+       fun is_nullable_to_not_null : Bool
+       do
+           return _from.is_nullable and not _to.is_nullable
+       end
+
+       redef fun == ( o )
+       do
+               return o isa MMImportedCast and
+                       o.from == from and o.to == to
+       end
+end
+
+# Method local properties
+redef class MMMethod
+       # casts explicitely imported to be available from native implementation
+       fun explicit_casts : Set[ MMImportedCast ] is abstract
+end