See also

- https://sicstus.sics.se/sicstus/docs/4.6.0/html/sicstus.html/lib_002dsets.html

To be done

- This library is incomplete. As of SICStus 4.6.0, the following predicates are missing:

• pairfrom/4
• power_set/2
• intersection/2
• symdiff/3
• setproduct/3
• union/2

 list_to_set(+List, -Set) is det

Set is List with all duplicates removed. Duplicates are removed by unification. This is not the same as SWI-Prolog's list_to_set/2 in library(lists), which finds duplicates based on term equality (==).

Compatibility

- SICStus 4

Re-exported predicates

The following predicates are exported from this file while their implementation is defined in imported modules or non-module files loaded by this module.

 is_set(@Set) is semidet

True if Set is a proper list without duplicates. Equivalence is based on ==/2. The implementation uses sort/2, which implies that the complexity is N*log(N) and the predicate may cause a resource-error. There are no other error conditions.

 intersection(+Set1, +Set2, -Set3) is det

True if Set3 unifies with the intersection of Set1 and Set2. The complexity of this predicate is |Set1|*|Set2|. A set is defined to be an unordered list without duplicates. Elements are considered duplicates if they can be unified.

See also

- ord_intersection/3.

 union(+Set1, +Set2, -Set3) is det

True if Set3 unifies with the union of the lists Set1 and Set2. The complexity of this predicate is |Set1|*|Set2|. A set is defined to be an unordered list without duplicates. Elements are considered duplicates if they can be unified.

See also

- ord_union/3

 subset(+SubSet, +Set) is semidet

True if all elements of SubSet belong to Set as well. Membership test is based on memberchk/2. The complexity is |SubSet|*|Set|. A set is defined to be an unordered list without duplicates. Elements are considered duplicates if they can be unified.

See also

- ord_subset/2.

 subtract(+Set, +Delete, -Result) is det

Delete all elements in Delete from Set. Deletion is based on unification using memberchk/2. The complexity is |Delete|*|Set|. A set is defined to be an unordered list without duplicates. Elements are considered duplicates if they can be unified.

See also

- ord_subtract/3.

Undocumented predicates

The following predicates are exported, but not or incorrectly documented.

 union(Arg1, Arg2, Arg3, Arg4)

 disjoint_union(Arg1, Arg2, Arg3)

 set_order(Arg1, Arg2, Arg3)

 seteq(Arg1, Arg2)

 intersect(Arg1, Arg2)

 disjoint(Arg1, Arg2)

 add_element(Arg1, Arg2, Arg3)

 del_element(Arg1, Arg2, Arg3)