Jan Burse, created Jun 25. 2019
* This module provides ordered maps. The ordered maps are
* represented by lists of key value pairs [k1-v1, .., kn-vn].
* The lists need to be key ordered and key duplicate free.
* If this precondition is violated the behaviour of the
* predicates is undefined.
* ?- ord_get([1-a,2-b], 2, X).
* X = b
* ?- ord_put([1-a,2-b], 2, c, X).
* X = [1-a,2-c]
* The realization uses a membership check based on (==)/2 and
* lexical ordering based on (@<)/2. As a result the predicates
* are safe to be used with non-ground terms. On the other hand,
* since this comparison is not arithmetical, 1 and 1.0 are for
* example considered different.
* An unordered map can be converted into an ordered map by
* using the ISO predicate keysort/2. Also there is no need for
* predicate permutation/2 here, since equality of ordered maps
* can be tested via the ISO predicate ==/2, provided the keys
* and values are sufficiently normalized.
* Warranty & Liability
* To the extent permitted by applicable law and unless explicitly
* otherwise agreed upon, XLOG Technologies GmbH makes no warranties
* regarding the provided information. XLOG Technologies GmbH assumes
* no liability that any problems might be solved with the information
* provided by XLOG Technologies GmbH.
* Rights & License
* All industrial property rights regarding the information - copyright
* and patent rights in particular - are the sole property of XLOG
* Technologies GmbH. If the company was not the originator of some
* excerpts, XLOG Technologies GmbH has at least obtained the right to
* reproduce, change and translate the information.
* Reproduction is restricted to the whole unaltered document. Reproduction
* of the information is only allowed for non-commercial uses. Selling,
* giving away or letting of the execution of the library is prohibited.
* The library can be distributed as part of your applications and libraries
* for execution provided this comment remains unchanged.
* Only to be distributed with programs that add significant and primary
* functionality to the library. Not to be distributed with additional
* software intended to replace any components of the library.
* Jekejeke is a registered trademark of XLOG Technologies GmbH.
* ord_get(M, K, V):
* The predicate succeeds for the value V associated with K
* in the ordered map M.
* ord_put(M, K, V, N):
* The predicate succeeds for an ordered map N where the value V is
* associated with the key K and the other key values are associated
* as in the ordered map M.
* ord_remove(M, K, N):
* The predicate succeeds for an ordered map N where the key K has
* no value and the other key values are associated as in the
* ordered map M.