Re: Questioning variable scoping in Lua

["Alex Davies" <alex.mania@...>]

Has been discussed many times before (google will show many counter 
examples).  By leaving it as globals, you can trap accesses (via 
metamethods) to undeclared variables which can help find those cases.  Also 
as an example of just one problem with local by default:

function ternary(cond, iftrue, iffalse)
 if cond then
   res = iftrue
 else
   res = iffalse
 end
 return res
end

How often would you forget to write local res at the top of that function? 
If you don't, (with local by default) it'd just return nil.  (Of course this 
is quite a contrived example, but it's not hard to see how often you'd still 
need to write "local" to ensure it has the scope of the correct block)

Besides, having to write local is still at least as easy as declaring c 
values at the top of their scope.

- Alex