arith: more functions in Int

src/arith/sidekick_arith.ml

@@ -6,6 +6,7 @@ module type NUM = sig
   val one : t
   val minus_one : t
 
+  val abs : t -> t
   val sign : t -> int
 
   val of_int : int -> t
@@ -35,6 +36,7 @@ module type INT = sig
   include NUM
 
   val succ : t -> t
+  val pred : t -> t
   val gcd : t -> t -> t
 end
 
@@ -72,3 +74,19 @@ module type RATIONAL = sig
   (** Pretty print rational with given amount of precision
       (for example as a floating point number) *)
 end
+
+module type INT_FULL = sig
+  include INT
+
+  val sqrt : t -> t
+
+  val divexact : t -> t -> t
+
+  val (/) : t -> t -> t
+
+  val rem : t -> t -> t
+
+  val probab_prime : t -> bool
+
+  val pow : t -> int -> t
+end

src/zarith/sidekick_zarith.ml

@@ -1,9 +1,15 @@
 
 
-module Int : Sidekick_arith.INT with type t = Z.t = struct
+module Int : Sidekick_arith.INT_FULL with type t = Z.t = struct
   include Z
   include Z.Compare
   let pp = pp_print
+  let divexact = divexact
+  let (/) = div
+  let probab_prime x = match probab_prime x 10 with
+    | 0 -> false
+    | 1 | 2 -> true
+    | _ -> assert false
 end
 
 module Rational

src/zarith/sidekick_zarith.mli

@@ -1,4 +1,4 @@
 
-module Int : Sidekick_arith.INT with type t = Z.t
+module Int : Sidekick_arith.INT_FULL with type t = Z.t
 
 module Rational : Sidekick_arith.RATIONAL with type t = Q.t and type bigint = Z.t