From 5d5b51dfc0400bc237e4415a36e6f6d8acbf723b Mon Sep 17 00:00:00 2001
From: Peter Simons <simons@cryp.to>
Date: Sun, 22 Feb 2015 20:42:08 +0100
Subject: [PATCH] haskell-generic-builder: add a passthru attribute
 'isHaskellLibrary' to every derivation

The presence of this attribute allows us to recognize Haskell derivations.
Furthermore, we can use it to distinguish libraries from executables (which is
useful for the code that's generating the wrapper).
---
 pkgs/development/haskell-modules/generic-builder.nix | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/pkgs/development/haskell-modules/generic-builder.nix b/pkgs/development/haskell-modules/generic-builder.nix
index 8e730fd37f03..6de62482751c 100644
--- a/pkgs/development/haskell-modules/generic-builder.nix
+++ b/pkgs/development/haskell-modules/generic-builder.nix
@@ -250,6 +250,8 @@ stdenv.mkDerivation ({
 
     inherit pname version;
 
+    isHaskellLibrary = hasActiveLibrary;
+
     env = stdenv.mkDerivation {
       name = "interactive-${optionalString hasActiveLibrary "haskell-"}${pname}-${version}-environment";
       nativeBuildInputs = [ ghcEnv systemBuildInputs ];