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--HG--
extra : rebase_source : 8689a0de277b66ffbe03ee0175c6722bb965a8ce
minor code simplification

--HG--
extra : rebase_source : be0db88eaeb028b031e5cd4016d6f3eb1e34df59
reformat some test code
implement lua_type() function that returns the Lua object type name