On Mon, Jul 14, 2008 at 10:49 PM, Tim Maxwell <timmaxw@gmail.com>
wrote:
Hi,
The environment system is a powerful new feature for Lua. It seems
to me
that the globals table accessible through LUA_GLOBALSINDEX is just
a special
case of the environment table - unless I am mistaken,
LUA_GLOBALSINDEX
simply refers to the environment table that was created for the
first Lua
state. If I'm wrong, disregard the rest of this message.
Perhaps LUA_GLOBALSINDEX is unnecessary. lua_getglobal and
lua_setglobal
could be redirected to access LUA_ENVIRONINDEX instead of
LUA_GLOBALSINDEX.
Most global variable access should go to the environment table
anyway, so
lua_getglobal and lua_setglobal would be more useful if they want
to the
environment table. Other functions that use LUA_GLOBALSINDEX
should probably
go to LUA_ENVIRONINDEX as well.
Can anybody think of a use for LUA_GLOBALSINDEX over
LUA_ENVIRONINDEX?
Is there anything that this change would break?
Is LUA_GLOBALSINDEX already being retired?
Tim Maxwell
LUA_GLOBALSINDEX is the environment of the running thread.
LUA_ENVIRONINDEX is useful for sharing an environment across many
userdata/functions in C (especially useful since C functions cannot
share upvalues). Usually, you will want to use LUA_GLOBALSINDEX.
--
-Patrick Donnelly
"One of the lessons of history is that nothing is often a good thing
to do and always a clever thing to say."
-Will Durant
