Index: src/Parser/parser.yy
===================================================================
--- src/Parser/parser.yy	(revision b66d14aaeea72bcdae48b4628ad29848b32691eb)
+++ src/Parser/parser.yy	(revision 454f478e4ba5abab2a66dcf28ad9efa8a5d7f313)
@@ -2441,5 +2441,9 @@
 type_parameter:											// CFA
 	type_class identifier_or_type_name
-		{ typedefTable.addToScope( *$2, TYPEDEFname, "9" ); }
+		{   typedefTable.addToScope( *$2, TYPEDEFname, "9" );
+			if ( $1 == TypeDecl::Otype ) { SemanticError( yylloc, "otype keyword is deprecated" ); }
+			if ( $1 == TypeDecl::Dtype ) { SemanticError( yylloc, "dtype keyword is deprecated" ); }
+			if ( $1 == TypeDecl::Ttype ) { SemanticError( yylloc, "ttype keyword is deprecated" ); }
+		}
 	  type_initializer_opt assertion_list_opt
 		{ $$ = DeclarationNode::newTypeParam( $1, $2 )->addTypeInitializer( $4 )->addAssertions( $5 ); }