# `arrangements`

This library provides predicates for generating and querying arrangements over lists. Arrangements are ordered selections of a given length with element repetition allowed. The following categories of predicates are provided:

- Generation operations - Predicates for generating arrangements.

- Ordering variants - Predicates that support an additional order argument (`default` or `lexicographic`) for controlling output order.

- Distinct-value generation - Predicates for generating arrangements while deduplicating equal-valued results.

- Indexed access - Predicates for direct access to arrangements at specific positions, including distinct arrangements.

- Lexicographic stepping - Predicates for navigating arrangements in lexicographic order.

- Counting operations - Predicates for counting arrangements and distinct arrangements.

- Random selection - Predicates for randomly selecting and sampling arrangements and distinct arrangements.

Dedicated `cartesian_products`, `permutations`, `combinations`, `multisets`, `derangements`, `partitions`, and `subsequences` libraries are also available for focused APIs on related operations.

## API documentation

Open the ../../apis/library_index.html#arrangements link in a web browser.

## Loading

To load all entities in this library, load the `loader.lgt` file:

    | ?- logtalk_load(arrangements(loader)).

## Testing

To test this library predicates, load the `tester.lgt` file:

    | ?- logtalk_load(arrangements(tester)).