ADDED: CLP(ℤ), Constraint Logic Programming over Integers

library(clpz) implements declarative integer arithmetic.

The most important predicates for reasoning about integers are:

    (#=)/2    equality
    (#\=)/2   disequality
    (#<)/2    less than
    (#>)/2    greater than
    (#=<)/2   less than or equal to
    (#>=)/2   greater than or equal to

In addition, the library provides several global constraints, such as
all_distinct/1 and global_cardinality/2, and reification predicates
that reflect the truth values of constraints into integer variables.

Enumeration predicates such label/1 and labeling/2 can be used to
search for solutions over finite domains.

Almost all Prolog programs also reason about integers. Therefore, I
recommend to add this library to your .scryerrc configuration file so
that declarative integer arithmetic is available in all your programs.

More information about CLP(ℤ):

    https://www.metalevel.at/prolog/clpz

Enjoy!

README.md

@@ -246,6 +246,11 @@ The modules that ship with Scryer Prolog are also called
 * [`reif`](src/prolog/lib/reif.pl)
   providing `if_/3`, `tfilter/3` and related predicates
   as described in *Indexing dif/2*.
+* [`clpz`](src/prolog/lib/clpz.pl)
+  CLP(ℤ): Constraint Logic Programming over Integers,
+  providing declarative integer arithmetic via `(#=)/2`, `(#\=)/2`,
+  `(#>=)/2` etc., and various global constraints and
+  enumeration predicates for solving combinatorial tasks.
 * [`pairs`](src/prolog/lib/pairs.pl)
   By convention, *pairs* are Prolog terms with
   principal functor `(-)/2`, written as `Key-Value`.