From 17f4883bfeb27c3fb6f28bd8ff8c6bbf65e6ea84 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <e.dolstra@tudelft.nl>
Date: Thu, 19 Oct 2006 17:43:58 +0000
Subject: [PATCH] * Better message.

---
 src/libexpr/primops.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc
index d5708f96b7..8118f84010 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -372,7 +372,7 @@ static Expr primToFile(EvalState & state, const ATermVector & args)
 
     for (PathSet::iterator i = context.begin(); i != context.end(); ++i) {
         if (isDerivation(*i))
-            throw EvalError("in `toFile': the file cannot refer to derivation outputs");
+            throw EvalError(format("in `toFile': the file `%1%' cannot refer to derivation outputs") % name);
         refs.insert(*i);
     }