From 3e45b61a9920466a8ea06b8ad9350d56ade435bc Mon Sep 17 00:00:00 2001
From: Profpatsch <mail@profpatsch.de>
Date: Mon, 6 Aug 2018 01:36:09 +0200
Subject: lib/trivial: add a few examples of usage of assertMsg/assertOneOf

---
 lib/lists.nix | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

(limited to 'lib/lists.nix')

diff --git a/lib/lists.nix b/lib/lists.nix
index 288882924ff..9a75f179e96 100644
--- a/lib/lists.nix
+++ b/lib/lists.nix
@@ -509,7 +509,8 @@ rec {
        => 3
   */
   last = list:
-    assert list != []; elemAt list (length list - 1);
+    assert assertMsg (list != []) "lists.last: list must not be empty!";
+    elemAt list (length list - 1);
 
   /* Return all elements but the last
 
@@ -517,7 +518,9 @@ rec {
        init [ 1 2 3 ]
        => [ 1 2 ]
   */
-  init = list: assert list != []; take (length list - 1) list;
+  init = list:
+    assert assertMsg (list != []) "lists.init: list must not be empty!";
+    take (length list - 1) list;
 
 
   /* return the image of the cross product of some lists by a function
-- 
cgit 1.4.1