creates a list with all solutions of a goal according to a given pattern.

findall(+Term, +Goal, ?TermList)

findall/3 unifies TermList with a list with as many instantiations of Term as Goal has solutions of Term.
If Goal does not succeed then TermList will be unified with the emtpy list.

Arguments

Term                   term
Goal                   goal
TermList               list

Examples

part_of(house, window).
part_of(house, door).
part_of(house, room).
part_of(room, table).
part_of(room, floor).
part_of(floor, tile).

contains(X, Y) :- part_of(X, Y).
contains(X, Y) :- part_of(X, Z), contains(Z, Y).

?- findall(Element, contains(What, Element), List).

Element = _1
What    = _2
List    = [window,door,room,table,floor,tile,table,floor,tile,tile]

?- setof(Element, contains(house, truck), List)

Element = _1
What    = _2
List    = []

Standard

This predicate is part of the ISO-Prolog Standard.

See also

bagof/3 , setof/3 , collect/3.

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