From 3c5971692a0edd8867b1c6f91598e0c403bf1376 Mon Sep 17 00:00:00 2001
From: Shea Levy <shea@shealevy.com>
Date: Thu, 12 Dec 2013 14:01:48 -0500
Subject: [PATCH] Simplify crossLists

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 lib/lists.nix | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/lib/lists.nix b/lib/lists.nix
index 561a657264bb..71a897027962 100644
--- a/lib/lists.nix
+++ b/lib/lists.nix
@@ -225,10 +225,5 @@ in rec {
 
   deepSeqList = xs: y: if any (x: deepSeq x false) xs then y else y;
 
-  crossLists = f: xss:
-    let
-      argss = fold (l: argss:
-        concatMap (arg: map (args: [ arg ] ++ args) argss) l
-      ) [[]] xss;
-    in map (args: foldl (f: arg: f arg) f args) argss;
+  crossLists = f: foldl (fs: args: concatMap (f: map f args) fs) [f];
 }