The Coq Proof Assistant

# Library Coq.extraction.ExtrHaskellZInt

Extraction of Z into Haskell's Int
Require Coq.extraction.Extraction.
Require Import ZArith.
Require Import ExtrHaskellZNum.

# Disclaimer: trying to obtain efficient certified programs

# by extracting Z into Int is definitively *not* a good idea.

# See comments in ExtrOcamlNatInt.v.

Extract Inductive positive => "Prelude.Int" [
"(\x -> 2 Prelude.* x Prelude.+ 1)"
"(\x -> 2 Prelude.* x)"
"1" ]
"(\fI fO fH n -> if n Prelude.== 1 then fH () else if Prelude.odd n then fI (n `Prelude.div` 2) else fO (n `Prelude.div` 2))".
Extract Inductive Z => "Prelude.Int" [ "0" "(\x -> x)" "Prelude.negate" ]
"(\fO fP fN n -> if n Prelude.== 0 then fO () else if n Prelude.> 0 then fP n else fN (Prelude.negate n))".