`dhall-nix`

For installation or development instructions, see:

dhall-haskell - README

Full documentation here:

dhall-nix instructions

Introduction

This dhall-nix package provides a Dhall to Nix compiler. You can use this compiler to program Nix using the Dhall language. This package targets people who wish Nix had a type system.

Quick start

If you have Nix installed then you can build and run this package using:

$ dhall-to-nix <<< "λ(x : Bool) → x == False"
x: x == false
$ dhall-to-nix <<< "{ foo = 1, bar = True }"
{ bar = true; foo = 1; }
$ dhall-to-nix <<< "< Left = 2 | Right : Natural >"
{ Left, Right }: Left 2

However, this package is also designed to be used directly from Nix. You can use the following dhallToNix utility to translate Dhall source code to the corresponding Nix expression directly within Nix:

dhallToNix = code :
  let
    file = builtins.toFile "dhall-expr" code;

    drv = pkgs.stdenv.mkDerivation {
      name = "dhall-expr-as-nix";

      buildCommand = ''
        dhall-to-nix <<< "${file}" > $out
      '';

      buildInputs = [ pkgs.haskellPackages.dhall-nix ];
    };
  in
    import "${drv}";

The above dhallToNix utility is now in nixpkgs so you can use pkgs.dhallToNix to transform Dhall expressions to Nix expressions

1.4 KiB Raw Blame History

dhall-nix

Introduction

Quick start

1.4 KiB

Raw Blame History

`dhall-nix`