diff --git a/lib/gvariant.nix b/lib/gvariant.nix
index 810e0db799bd..d47d5120ef9a 100644
--- a/lib/gvariant.nix
+++ b/lib/gvariant.nix
@@ -194,11 +194,12 @@ rec {
       vs = map mkValue (
         if elems == [ ] then throw "Please create empty array with mkEmptyArray." else elems
       );
+      firstType = (head vs).type;
       elemType =
-        if lib.any (t: (head vs).type != t) (map (v: v.type) vs) then
+        if lib.any (v: v.type != firstType) vs then
           throw "Elements in a list should have same type."
         else
-          (head vs).type;
+          firstType;
     in
     mkPrimitive (type.arrayOf elemType) vs
     // {