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+(**
+ * Efficient (but uncertified) extraction of usual [Z] functions
+ * into equivalent versions in Haskell's Prelude that are defined
+ * for any [Num] typeclass instances.  Useful in combination with
+ * [Extract Inductive Z] that maps [Z] onto a Haskell type that
+ * implements [Num].
+ *)
+
+Require Import ZArith.
+Require Import EqNat.
+
+Extract Inlined Constant Z.add => "(Prelude.+)".
+Extract Inlined Constant Z.sub => "(Prelude.-)".
+Extract Inlined Constant Z.mul => "(Prelude.*)".
+Extract Inlined Constant Z.max => "Prelude.max".
+Extract Inlined Constant Z.min => "Prelude.min".
+Extract Inlined Constant Z_ge_lt_dec => "(Prelude.>=)".
+Extract Inlined Constant Z_gt_le_dec => "(Prelude.>)".
+
+Extract Constant Z.div => "(\n m -> if m Prelude.== 0 then 0 else Prelude.div n m)".
+Extract Constant Z.modulo => "(\n m -> if m Prelude.== 0 then 0 else Prelude.mod n m)".