From a37b9a291a40d0087321d57650b4f79da624f376 Mon Sep 17 00:00:00 2001
From: Tom van Dijck <tvandijck@blizzard.com>
Date: Thu, 30 Nov 2017 10:01:07 -0800
Subject: [PATCH] fix table.insertkeyed

---
 src/base/table.lua | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/base/table.lua b/src/base/table.lua
index 4e8c3c6e..fed93757 100644
--- a/src/base/table.lua
+++ b/src/base/table.lua
@@ -255,7 +255,7 @@
 
 --
 -- Inserts a value into a table as both a list item and a key-value pair.
--- Useful for set operations.
+-- Useful for set operations. Returns false if the value already exists, true otherwise.
 --
 
 	function table.insertkeyed(tbl, pos, value)
@@ -263,8 +263,14 @@
 			value = pos
 			pos = #tbl + 1
 		end
+
+		if tbl[value] ~= nil then
+			return false
+		end
+
 		table.insert(tbl, pos, value)
 		tbl[value] = value
+		return true
 	end