From a1d4a00dcdcbe8bae546f055b1c5fa21ea87bce4 Mon Sep 17 00:00:00 2001
From: Peter Simons <simons@cryp.to>
Date: Fri, 29 Mar 2013 16:35:50 +0100
Subject: [PATCH] haskell-snap: jailbreak to support building with lens 3.9.0.2

---
 pkgs/development/libraries/haskell/snap/snap.nix | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/pkgs/development/libraries/haskell/snap/snap.nix b/pkgs/development/libraries/haskell/snap/snap.nix
index f5da92f6c8e..8462b85caf9 100644
--- a/pkgs/development/libraries/haskell/snap/snap.nix
+++ b/pkgs/development/libraries/haskell/snap/snap.nix
@@ -20,6 +20,9 @@ cabal.mkDerivation (self: {
     unorderedContainers vector vectorAlgorithms xmlhtml
   ];
   jailbreak = true;
+  patchPhase = ''
+    sed -i -e 's|lens .*>= 3.7.6.*$|lens|' snap.cabal
+  '';
   meta = {
     homepage = "http://snapframework.com/";
     description = "Top-level package for the Snap Web Framework";