/* Probleme du choix distant: Choix interne  */ 


chan s, a, b ;

process Left{
state idle, choice, before_a, before_b;
urgent idle, choice, before_a, before_b;
init idle;
trans idle -> choice{sync s!; },
choice -> before_a{},
choice -> before_b{},
before_a -> idle{sync a!; },
before_b -> idle{sync b?; };
}
process Right{
state idle, choice, before_a, before_b;
urgent idle, choice, before_a, before_b;
init idle;
trans idle -> choice{sync s?; },
choice -> before_a{},
choice -> before_b{},
before_a -> idle{sync a?; },
before_b -> idle{sync b!; };
}
gauche := Left();
droit :=  Right();

system gauche, droit;