diff --git a/.bam/functions.lua b/.bam/functions.lua
index e5203e0..3159891 100644
--- a/.bam/functions.lua
+++ b/.bam/functions.lua
@@ -42,11 +42,15 @@ function host_system()
 	return nil
 end
 
+function SetSettingsPrefix(settings, prefix)
+	settings.labelprefix = string.format("[%s] ", prefix)
+end
+
 -- Copy settings with a optional label prefix.
 function CopySettings(settings, prefix)
 	local n = TableDeepCopy(settings)
 	if prefix ~= nil then
-		n.labelprefix = string.format("[%s] ", prefix)
+		SetSettingsPrefix(n, prefix)
 	end
 	return n
 end