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 lists.pl -- SICStus 3-compatible library(lists).
- https://sicstus.sics.se/sicstus/docs/3.12.11/html/sicstus/Lists.html
To be done
- This library is incomplete. As of SICStus 3.12.11, the following predicates are missing:
substitute(+OldElem, +List, +NewElem, -NewList) is det
NewList is List with all values that are identical (==) to OldElem replaced by NewElem.
nth(?Index, ?List, ?Element) is nondet
True if Element is the N-th element in List. Counting starts at 1.
deprecated
- use nth1/3.
nth(?Index, ?List, ?Element, ?Rest) is nondet
True if Element is the N-th element in List and Rest is the remainder (as if by select/3) of List. Counting starts at 1.
deprecated
- use nth1/4.
same_length(?List1, ?List2, ?Length) is nondet
True if List1 and List2 both have length Length.
sublist(?Sub, +List)
True when all members of Sub are members of List in the same order.
Compatibility
- sicstus. The order of generating sublists differs.
- This predicate is known in many Prolog implementations, but the semantics differ. E.g. In YAP it is a continuous sub-list.
suffix(?Suffix, ?List) is nondet
True if Suffix is a suffix of List. Not the same as suffix/2 in SICStus 4 - the arguments are reversed!

## Re-exported predicates

The following predicates are re-exported from other modules

min_list(+List:list(number), -Min:number) is semidet
True if Min is the smallest number in List. Fails if List is empty.
- min_member/2.
permutation(?Xs, ?Ys) is nondet
True when Xs is a permutation of Ys. This can solve for Ys given Xs or Xs given Ys, or even enumerate Xs and Ys together. The predicate permutation/2 is primarily intended to generate permutations. Note that a list of length N has N! permutations, and unbounded permutation generation becomes prohibitively expensive, even for rather short lists (10! = 3,628,800).

If both Xs and Ys are provided and both lists have equal length the order is |Xs|^2. Simply testing whether Xs is a permutation of Ys can be achieved in order log(|Xs|) using msort/2 as illustrated below with the `semidet` predicate is_permutation/2:

```is_permutation(Xs, Ys) :-
msort(Xs, Sorted),
msort(Ys, Sorted).```

The example below illustrates that Xs and Ys being proper lists is not a sufficient condition to use the above replacement.

```?- permutation([1,2], [X,Y]).
X = 1, Y = 2 ;
X = 2, Y = 1 ;
false.```
Errors
- `type_error(list, Arg)` if either argument is not a proper or partial list.
reverse(?List1, ?List2)
Is true when the elements of List2 are in reverse order compared to List1. This predicate is deterministic if either list is a proper list. If both lists are partial lists backtracking generates increasingly long lists.
same_length(?List1, ?List2)
Is true when List1 and List2 are lists with the same number of elements. The predicate is deterministic if at least one of the arguments is a proper list. It is non-deterministic if both arguments are partial lists.
- length/2
sum_list(+List, -Sum) is det
Sum is the result of adding all numbers in List.
delete(+List1, @Elem, -List2) is det
Delete matching elements from a list. True when List2 is a list with all elements from List1 except for those that unify with Elem. Matching Elem with elements of List1 is uses ```\+ Elem \= H```, which implies that Elem is not changed.
- select/3, subtract/3.
deprecated
- There are too many ways in which one might want to delete elements from a list to justify the name. Think of matching (= vs. ==), delete first/all, be deterministic or not.
last(?List, ?Last)
Succeeds when Last is the last element of List. This predicate is `semidet` if List is a list and `multi` if List is a partial list.
Compatibility
- There is no de-facto standard for the argument order of last/2. Be careful when porting code or use `append(_, [Last], List)` as a portable alternative.
nth0(?N, ?List, ?Elem, ?Rest) is det
Select/insert element at index. True when Elem is the N'th (0-based) element of List and Rest is the remainder (as in by select/3) of List. For example:
```?- nth0(I, [a,b,c], E, R).
I = 0, E = a, R = [b, c] ;
I = 1, E = b, R = [a, c] ;
I = 2, E = c, R = [a, b] ;
false.```
```?- nth0(1, L, a1, [a,b]).
L = [a, a1, b].```
member(?Elem, ?List)
True if Elem is a member of List. The SWI-Prolog definition differs from the classical one. Our definition avoids unpacking each list element twice and provides determinism on the last element. E.g. this is deterministic:
`    member(X, [One]).`
author
- Gertjan van Noord
nextto(?X, ?Y, ?List)
True if Y directly follows X in List.
append(?List1, ?List2, ?List1AndList2)
List1AndList2 is the concatenation of List1 and List2
nth0(?Index, ?List, ?Elem)
True when Elem is the Index'th element of List. Counting starts at 0.
Errors
- `type_error(integer, Index)` if Index is not an integer or unbound.
- nth1/3.
select(?Elem, ?List1, ?List2)
Is true when List1, with Elem removed, results in List2. This implementation is determinsitic if the last element of List1 has been selected.
prefix(?Part, ?Whole)
True iff Part is a leading substring of Whole. This is the same as `append(Part, _, Whole)`.
max_list(+List:list(number), -Max:number) is semidet
True if Max is the largest number in List. Fails if List is empty.