From 98a0a257e0597d23afa5b1cab88e2ce42e65d4fd Mon Sep 17 00:00:00 2001
From: Michael Raskin <7c6f434c@mail.ru>
Date: Sat, 27 Oct 2007 17:54:20 +0000
Subject: [PATCH] Added sumArgs - it takes a function and gives a function to
 accpet any number of arguments and then (after getting null) apply original
 function to the resulting attribute set.

svn path=/nixpkgs/trunk/; revision=9542
---
 pkgs/lib/default.nix | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pkgs/lib/default.nix b/pkgs/lib/default.nix
index 1a5dddecdfe..e631bca4c60 100644
--- a/pkgs/lib/default.nix
+++ b/pkgs/lib/default.nix
@@ -9,6 +9,10 @@ in
 
 rec {
 
+  innerSumArgs = f : x : y : (if y == null then (f x)
+	else (innerSumArgs f (x // y)));
+  sumArgs = f : innerSumArgs f {};
+
   # "Fold" a binary function `op' between successive elements of
   # `list' with `nul' as the starting value, i.e., `fold op nul [x_1
   # x_2 ... x_n] == op x_1 (op x_2 ... (op x_n nul))'.  (This is