let declare d =
let m = the_model () in
if Iset.mem d.d_name m.model_locked then
Wp_parameters.fatal "Locked symbol '%a'" LogicId.pretty d.d_name ;
m.model_updated <- true ;
Ihmap.replace m.model_index d.d_name {
r_declaration = d ;
r_age = m.model_history ;
r_localdeps = dependencies d.d_item ;
}