The origin auxiliar is part of luasocket, it's a general purpose class implemention lib for userdata with metatable.
/*=========================================================================*\
* Auxiliar routines for class hierarchy manipulation
* LuaSocket toolkit (but completely independent of other LuaSocket modules)
*
* A LuaSocket class is a name associated with Lua metatables. A LuaSocket
* group is a name associated with a class. A class can belong to any number
* of groups. This module provides the functionality to:
*
* - create new classes
* - add classes to groups
* - set the class of objects
* - check if an object belongs to a given class or group
* - get the userdata associated to objects
* - print objects in a pretty way
*
* LuaSocket class names follow the convention <module>{<class>}. Modules
* can define any number of classes and groups. The module tcp.c, for
* example, defines the classes tcp{master}, tcp{client} and tcp{server} and
* the groups tcp{client,server} and tcp{any}. Module functions can then
* perform type-checking on their arguments by either class or group.
*
* LuaSocket metatables define the __index metamethod as being a table. This
* table has one field for each method supported by the class, and a field
* "class" with the class name.
*
* The mapping from class name to the corresponding metatable and the
* reverse mapping are done using lauxlib.
\*=========================================================================*/
I do minimual change, and add a few APIs for lui and lua-openssl. TODO more
LuaSocket 3.0 license
Copyright © 2004-2018 Diego Nehab
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