c_main.chr

:- module(bacmain, [tag/2]).
:- use_module(modA).
:- use_module(modB).
:- chr_constraint tag/2.

% Atoms unique to a single module canonicalize to that module's
% qualified form. Atoms shared between modules stay unqualified
% (since the renamer can't pick a unique source).
tag(only_in_a, R) <=> R = a.
tag(only_in_b, R) <=> R = b.
tag(box, R)       <=> R = b.
tag(_, R)         <=> R = other.