/*************************************************************************
* *
* YAP Prolog *
* Yap Prolog was developed at NCCUP - Universidade do Porto *
* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997 *
**************************************************************************
* File: protect.yap *
* Last rev: *
* mods: *
* comments: protecting the system functions *
*************************************************************************/
% This protects all code from further changes
% and also makes it impossible from some predicates to be seen
'$protect' :-
current_atom(Name),
'$make_system_preds'(Name),
atom_codes(Name,[36|_]),
'$hide'(Name).
'$protect'.
'$make_system_preds'('$directive') :- !.
'$make_system_preds'('$meta_predicate') :- !.
'$make_system_preds'('$exec_directive') :- !.
'$make_system_preds'(goal_expansion) :- !.
'$make_system_preds'(term_expansion) :- !.
'$make_system_preds'(portray) :- !.
'$make_system_preds'(library_directory) :- !.
'$make_system_preds'(modules_with_attributes) :- !.
'$make_system_preds'(woken_att_do) :- !.
'$make_system_preds'(convert_att_var) :- !.
'$make_system_preds'(Name) :-
% '$format'("~NProtecting ~a",Name),
'$pred_defined_for'(Name,Pred),
% '$format'("~NProtecting ~q",Pred),
'$protect_system_pred'(Pred),
fail.
'$make_system_preds'(_).
'$protect_system_pred'(Pred) :-
'$flags'(Pred,OldFlags,OldFlags\/8'40000).
% hide all atoms who start by '$'
'$hide'('$VAR') :- !, fail. /* not $VAR */
'$hide'('$stream') :- !, fail. /* not $STREAM */
'$hide'('$stream_position') :- !, fail. /* not stream position */
'$hide'(Name) :- hide(Name), fail.
