I am trying to analyze this websocket ++ example https://github.com/zaphoyd/websocketpp/blob/experimental/examples/broadcast_server/broadcast_server.cpp
Line 126 is typedef std::set<connection_hdl,std::owner_less<connection_hdl>> con_list;. I wonder why this is not easy typedef std::set<connection_hdl> con_list;.
typedef std::set<connection_hdl,std::owner_less<connection_hdl>> con_list;
typedef std::set<connection_hdl> con_list;
I read How Comma Operator and http://en.cppreference.com/w/cpp/memory/owner_less work, but I'm not sure what the purpose is.
What is actually stored in std::set? What does std::owner_lessit really do? What is the purpose of creating a container with this structure instead of saving connection_hdl?
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std::owner_less
connection_hdl
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