Library Coq.extraction.ExtrHaskellZInteger

Extraction of Z into Haskell's Integer

Require Coq.extraction.Extraction.

Require Import ZArith.
Require Import ExtrHaskellZNum.

Disclaimer: trying to obtain efficient certified programs by extracting Z into Integer isn't necessarily a good idea. See comments in ExtrOcamlNatInt.v.

Extract Inductive positive => "Prelude.Integer" [
  "(\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.Integer" [ "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))".