<language> (Doc) A language related to Oc.
["Programming Language Doc and Its Self-Description, or 'X=X Is Considered
Harmful'", M. Hirata, Proc 3rd Conf Japan Soc Soft Sci Tech, pp. 69-72, 1986].
Direct Connection « directed acyclic graph «
directed graph « Directed Oc » directed set »
Direct Inward Dialing » directional coupler