An interface between Prologapplication programs and the X Window SYstem that aims to be independent from the Prologengine, provided that it has a Quintus {foreign function} interface (e.g. {SICStus} and {YAP}). It is mostlY written in Prolog and is divided in two libraries: Edipo - the lower level interface to the Xlib functions and Ytoolkit - the higher level user interface toolkit. . E-mail: Ze' Paulo Leal . (1993-03-02)