Dictionary: module {	PATH: con "/dis/lib/dict.dis"; 	Dict: adt {		entries: list of (string, string); 		add:	fn( d: self ref Dict, e: (string, string) );		delete:	fn( d: self ref Dict, k: string );		lookup:	fn( d: self ref Dict, k: string ) :string;		keys:	fn( d: self ref Dict ): list of string;	};  };