* error message *)
exception Error of int * int * string
- (** lexer for concrete syntax patterns (notation level 1) *)
-val syntax_pattern_lexer: (string * string) Token.glexer
+val level1_pattern_lexer: (string * string) Token.glexer
+val level2_ast_lexer: (string * string) Token.glexer
+val level2_meta_lexer: (string * string) Token.glexer
- (** lexer for ast patterns (notation level 2) *)
-val ast_pattern_lexer: (string * string) Token.glexer
+val add_level2_ast_keyword: string -> unit (** non idempotent *)
+val remove_level2_ast_keyword: string -> unit (** non idempotent *)