util.set: Change tostring format to {a, b, c}

Makes it easier to make out where the set starts and ends in cases where
it may get embedded and tostring()-ed in a log message.

{ } taken over from util.array for consistency with some other systems
syntax for Sets, e.g. Python

1 files changed, 1 insertions, 1 deletions

diff --git a/util/set.lua b/util/set.lua
index a2704f6c..dbff28b4 100644
--- a/util/set.lua
+++ b/util/set.lua
@@ -186,7 +186,7 @@ function set_mt.__tostring(set)
 	for item in pairs(items) do
 		s[#s+1] = tostring(item);
 	end
-	return t_concat(s, ", ");
+	return "{"..t_concat(s, ", ").."}";
 end
 
 function set_mt.__freeze(set)