--- a/Lib/IMPL/SQL/Schema/Column.pm	Thu May 02 10:43:49 2013 +0400
+++ b/Lib/IMPL/SQL/Schema/Column.pm	Tue May 07 02:19:24 2013 +0400
@@ -5,6 +5,9 @@
 use IMPL::Exception();
 use IMPL::Const qw(:prop);
 use IMPL::declare {
+    require => {
+        SchemaType => '-IMPL::SQL::Schema::Type'
+    },
     base => [
         'IMPL::Object' => undef,
         'IMPL::Object::Autofill' => '@_'
@@ -26,7 +29,7 @@
     
     $this->{$isNullable} ||= 0; # if not exists $this->{$isNullable};
     
-    is( $this->{$type}, typeof IMPL::SQL::Schema::Type) or
+    is( $this->{$type}, SchemaType) or
         die new IMPL::InvalidArgumentException('a type is required for the column',$this->{$name});
 }