/**
* Warranty & Liability
* To the extent permitted by applicable law and unless explicitly
* otherwise agreed upon, XLOG Technologies AG makes no warranties
* regarding the provided information. XLOG Technologies AG assumes
* no liability that any problems might be solved with the information
* provided by XLOG Technologies AG.
*
* Rights & License
* All industrial property rights regarding the information - copyright
* and patent rights in particular - are the sole property of XLOG
* Technologies AG. If the company was not the originator of some
* excerpts, XLOG Technologies AG has at least obtained the right to
* reproduce, change and translate the information.
*
* Reproduction is restricted to the whole unaltered document. Reproduction
* of the information is only allowed for non-commercial uses. Selling,
* giving away or letting of the execution of the library is prohibited.
* The library can be distributed as part of your applications and libraries
* for execution provided this comment remains unchanged.
*
* Restrictions
* Only to be distributed with programs that add significant and primary
* functionality to the library. Not to be distributed with additional
* software intended to replace any components of the library.
*
* Trademarks
* Jekejeke is a registered trademark of XLOG Technologies AG.
*/
/**
* deref(S, T):
* The predicate succeeds in T with the value of the term S.
*/
% deref(+Term, -Term)
deref('$ATTR'(V,_), W) :- !, V = W.
deref(V, V).
/**
* freeze(T, G):
* The predicate delays the goal G on the term T.
*/
% freeze(+Term, +Goal)
freeze('$ATTR'(V,L), G) :- var(V), !, sys_attr_freeze(L, G).
freeze(_, G) :- G.
% sys_attr_freeze(+List, +Goal)
sys_attr_freeze(V, G) :- var(V), !, V = [G|_].
sys_attr_freeze([_|L], G) :- sys_attr_freeze(L, G).
/**
* bind(T, S):
* The predicate succeeds when the frozen goals of T
* succeed after binding S to T.
*/
% bind(+Term, +Term)
bind('$ATTR'(V,L), W) :- var(V), !,
sys_attr_bind(L, R),
'$SEQ'(nothing,[V = W|R]).
bind(V, W) :-
deref(V, W).
% sys_attr_bind(+List)
sys_attr_bind(V, []) :- var(V), !.
sys_attr_bind([G|L], [H|R]) :- ir_site_new(G, H), sys_attr_bind(L, R).