Add the shell.nix

1 files changed, 25 insertions, 0 deletions

diff --git a/shell.nix b/shell.nix
new file mode 100644
index 0000000..733234f
--- /dev/null
+++ b/shell.nix
@@ -0,0 +1,25 @@
+{ compiler ? "default", doBenchmark ? false }:
+
+let
+  config = {
+    packageOverrides = pkgs: rec {
+      haskellPackages = pkgs.haskellPackages.override {
+        overrides = haskellPackagesNew: haskellPackagesOld: rec {
+          hedgehog-fn = haskellPackagesNew.callPackage ./nix/hedgehog-fn.nix {};
+          tomland = haskellPackagesNew.callPackage ./nix/tomland.nix {};
+          parser-combinators = haskellPackagesNew.callPackage ./nix/parser-combinators.nix {};
+        };
+      };
+    };
+  };
+  pkgs = import <nixpkgs> { inherit config; };
+
+  haskellPackages = if compiler == "default"
+                       then pkgs.haskellPackages
+                       else pkgs.haskell.packages.${compiler};
+
+  variant = if doBenchmark then pkgs.haskell.lib.doBenchmark else pkgs.lib.id;
+
+  drv = variant (haskellPackages.callPackage (import ./.) {});
+in
+  if pkgs.lib.inNixShell then drv.env else drv