diff -r 55e927a6c228 -r 07c10f9ba77c minify/optlex.lua
--- a/minify/optlex.lua	Wed Feb 10 12:33:42 2016 +0000
+++ b/minify/optlex.lua	Fri May 05 09:44:05 2017 +0100
@@ -830,3 +830,5 @@
   if opt_details and opt_details > 0 then print() end -- spacing
   return stoks, sinfos, stoklns
 end
+
+return _M;