Unlocked References not supported by Lua5

[virgil@... (Virgil Smith)]

I find the following in Lua.h...
#define lua_ref(L,lock)	((lock) ? luaL_ref(L, LUA_REGISTRYINDEX) : \
      (lua_pushstring(L, "unlocked references are obsolete"), lua_error(L),
0))

1. This is not listed in the API changes section of the Lua5 manual.

2. Why was this feature removed?

3. I see a way to properly implement Lua4 style references using 2 (or 3)
tables inside the registry (with one of the tables having weak values), but
this is going to be tedious to implement (and I made EXTENSIVE use of
unlocked references in most all of my Lua4 code, so implementing this is
important to me.
Has anyone already implemented this (and if so will they make it available)?

=====================================================
Virgil Smith               EMAIL: Virgil@Nomadics.com
Nomadics Inc               HTTP:  www.Nomadics.com
1024 S. Innovation Way     PHONE: 405-372-9535
Stillwater, OK 74074, USA  FAX:   405-372-9537
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