From 8191992c83bf4387b03c5fdaba818dc2b520462d Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <edolstra@gmail.com>
Date: Wed, 25 Oct 2017 15:18:37 +0200
Subject: [PATCH] Bump language version

---
 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 afd344286..6a50c9934 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -2008,7 +2008,7 @@ void EvalState::createBaseEnv()
        language feature gets added.  It's not necessary to increase it
        when primops get added, because you can just use `builtins ?
        primOp' to check. */
-    mkInt(v, 4);
+    mkInt(v, 5);
     addConstant("__langVersion", v);
 
     // Miscellaneous