diff --git a/index.html b/index.html
index c2b6bde..51b2d17 100644
--- a/index.html
+++ b/index.html
@@ -4894,7 +4894,7 @@ Line 12 makes a custom GHC that knows about pandoc-columns,
and line 17 uses the custom GHC as a build input for this flake.
-
Here’s a short Haskell program that uses it.
+
Here’s a short Haskell program that uses the new flake.
Main.hs
@@ -5644,7 +5644,7 @@ Hello from your flake!
diff --git a/source/recipes/devshell/haskell-flake/flake.nix b/source/recipes/devshell/haskell-flake/flake.nix
index b093b2a..331af5e 100644
--- a/source/recipes/devshell/haskell-flake/flake.nix
+++ b/source/recipes/devshell/haskell-flake/flake.nix
@@ -1,34 +1,21 @@
{
- description = "Pandoc build system for maths web";
-
inputs = {
- nixpkgs.url = "github:nixos/nixpkgs/nixpkgs-unstable";
- flake-parts.url = "github:hercules-ci/flake-parts";
- haskell-flake.url = "github:srid/haskell-flake";
- pandoc-linear-table.url = "/home/amy/github/pandoc-linear-table";
- pandoc-logic-proof.url = "/home/amy/github/pandoc-logic-proof";
- pandoc-columns.url = "/home/amy/github/pandoc-columns";
- pandoc-query.url = "/home/amy/codeberg/pandoc-query";
+ nixpkgs.url = "github:NixOS/nixpkgs";
+ flake-utils.url = "github:numtide/flake-utils";
};
- outputs = inputs@{ self, nixpkgs, flake-parts, pandoc-linear-table, pandoc-logic-proof, pandoc-columns, pandoc-query, ... }:
- flake-parts.lib.mkFlake { inherit inputs; } {
- systems = nixpkgs.lib.systems.flakeExposed;
- imports = [ inputs.haskell-flake.flakeModule ];
-
- perSystem = { self', pkgs, ... }: {
- haskellProjects.default = {
- # use my versions of some Haskell pagkages instead of the nixpkgs versions
- packages = {
- pandoc-linear-table.source = inputs.pandoc-linear-table;
- pandoc-logic-proof.source = inputs.pandoc-logic-proof;
- pandoc-columns.source = inputs.pandoc-columns;
- pandoc-query.source = inputs.pandoc-query;
- };
- };
-
- # haskell-flake doesn't set the default package, but you can do it here.
- packages.default = self'.packages.pandoc-maths-web;
- };
- };
+ outputs = { self, nixpkgs, flake-utils, pandoc-columns }:
+ flake-utils.lib.eachDefaultSystem (system:
+ let
+ pkgs = import nixpkgs { inherit system; };
+ customGhc = pkgs.haskellPackages.ghcWithPackages (p: with p; [ extra ]);
+ in
+ {
+ devShells = rec {
+ default = pkgs.mkShell {
+ buildInputs = [ customGhc ];
+ };
+ };
+ }
+ );
}
diff --git a/source/recipes/devshell/haskell-flake/main.adoc0 b/source/recipes/devshell/haskell-flake/main.adoc0
index 14b1f51..5f4a8a1 100644
--- a/source/recipes/devshell/haskell-flake/main.adoc0
+++ b/source/recipes/devshell/haskell-flake/main.adoc0
@@ -1,4 +1,4 @@
-= Access to a Haskell package defined in a flake
+= Access to a Haskell package defined in a flake (without using a `.cabal` file)
////
$ mkdir tempwork
@@ -10,43 +10,46 @@ $ git add flake.lock
$ git commit -a -m temp
////
+Occasionally you might want to run a short Haskell program that depends on a Haskell library,
+but you don't want to bother writing a cabal file.
+In this example we will access a Haskell package called `pandoc-columns`)
+that is defined in a flake in a remote git repo.
-In this example we will access three Haskell packages
-(`pandoc-linear-table`, `pandoc-logic-proof`, and `pandoc-columns`)
-that are defined as flakes on my hard drive.
-We are using `haskell-flake`, so the development environment is
-set up automatically; no need to define `devShells`.
+[NOTE]
+====
+For non-trivial Haskell development projects,
+it's usually more convenient to use `haskell-flake` as described in <<#haskell-flake>>,
+together with the _high-level workflow_ described in <<_development_workflows>>.
+====
-[source,nix,linenums]
+[source,nix,linenums,highlight='5,8,12,17']
.flake.nix
....
include::flake.nix[]
....
-Here's a demonstration using the shell.
+Line 5 adds `pandoc-columns` as an input to this flake.
+Line 8 allows the output function to reference `pandoc-columns`.
+Line 12 makes a custom GHC that knows about `pandoc-columns`,
+and line 17 uses the custom GHC as a build input for this flake.
+
+Here's a short Haskell program that uses the new flake.
+
+[source,haskell,linenums]
+.Main.hs
+....
+include::Main.hs[]
+....
+
+Here's a demonstration using the program.
....
+$ runghc Main.hs # Fails; dependency not available
$# ../../../../../start-shell nix develop <