Clarification needed: naming conventions

[Lorenzo Donati <lorenzodonatibz@...>]

Hi all!

Lua 5.1.4. manual says:

"As a convention, names starting with an underscore followed by 
uppercase letters (such as _VERSION) are reserved for internal global 
variables used by Lua."

I have three doubts about that sentence:

1.Are the reserved names all those with an underscore followed by _ALL_ 
uppercase letters? I.e. is for example _Version to be considered reserved?

2. Is the underscore itself to be considered an uppercase letter? I.e. 
is __VERSION (two underscores at the beginning) to be considered reserved?

3. The sentence makes an explicit reference to the global scope. Does 
this mean that I'm free to use mytable._VERSION without violating the 
convention?

thanks

-- Lorenzo