%%%%%% Proposed Twelf Standard Library
%%%%%% John Boyland
%%%%%% You may freely use, modify and distribute this file without restrictions.

%{%
This file includes some simple types that should
be standardized.  Here's my proposal.
%}%




%%%% Structure



%%% The uninhabited type


void : type.


%freeze void.




%%% The uninteresting type


unit : type.


unit/ : unit.


%freeze unit.



%%% The three-way comparison type


comp : type.


less    : comp.

greater : comp.

equal   : comp.


%freeze comp.