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maplist(+Pred, ?OldList, ?NewList)

Succeeds if Pred(Old, New) succeeds for corresponding pairs of elements from OldList and NewList.
+Pred
Atom or compound term.
?OldList
List or variable.
?NewList
List or variable.

Description

Either OldList or NewList should be a proper list. maplist/3 succeeds if for every corresponding pair of elements Old, New of the two lists OldList and NewList the invocation of Pred with two aditional arguments Old and New succeeds.

The definition of this Prolog library predicate is:

:- tool(maplist/3, maplist_body/4).

maplist_body(_, [], [], _).
maplist_body(Pred, [H1|T1], [H2|T2], M) :-
    Pred =.. PL,
    append(PL, [H1, H2], NewPred),
    Call =.. NewPred,
    call(Call, M),
    maplist_body(Pred, T1, T2, M).
This predicate does not perform any type testing functions.

Modes and Determinism

Modules

This predicate is sensitive to its module context (tool predicate, see @/2).

Fail Conditions

Fails if at least for one pair of corresponding elements of OldList and NewList the invocation of Pred with these two additional arguments fails

Resatisfiable

Resatisfiable if at least for one pair of corresponding elements of OldList and NewList the invocation of Pred with these two additional arguments is resatisfiable

Examples

Success:
  maplist(integer_atom, [1, 2, 3], ['1', '2', '3']).
  maplist(sin, [0, 1, 2], X).
      (gives X = [0.0, 0.841471, 0.909297])
  maplist(get_flag(var/1), [skip, type, spy], [off, built_in, off]).
Fail:
  maplist(type_of, [1, a, "a"], [integer, atom, atom]).



See Also

checklist / 2