From 8bdc1503c103972d64279d1eadc0ab44a56140af Mon Sep 17 00:00:00 2001
From: Michael Raskin <7c6f434c@mail.ru>
Date: Fri, 28 Aug 2009 07:00:40 +0000
Subject: [PATCH] Put the meta-based choice in suspended state to be used
 automatically when tryEval is available

svn path=/nixpkgs/trunk/; revision=16886
---
 pkgs/top-level/release.nix | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/pkgs/top-level/release.nix b/pkgs/top-level/release.nix
index c3ea3845a44..0663fe12218 100644
--- a/pkgs/top-level/release.nix
+++ b/pkgs/top-level/release.nix
@@ -34,10 +34,13 @@ let
       in testOn job.systems getPkg);
 
   selectMaintained = attrSet: let
-    pairs = pkgs.lib.concatMap 
-      (x: let val = builtins.tryEval (processPackage (builtins.getAttr x attrSet)); in
-        if val.success && val.value != [] then [{name=x; value=val.value;}] else [])
-      (builtins.attrNames attrSet);
+    if builtins  ? tryEval then 
+      pairs = pkgs.lib.concatMap 
+        (x: let val = builtins.tryEval (processPackage (builtins.getAttr x attrSet)); in
+          if val.success && val.value != [] then [{name=x; value=val.value;}] else [])
+        (builtins.attrNames attrSet);
+    else
+      [];
     in
       builtins.listToAttrs pairs;
   # May fail as much as it wishes, we will catch the error