Nil for Local Variable

[Dong Feng <middle.fengdong@...>]

It is said, if you assign "nil" to a global variable, or to an item of a table, you make that variable/item non-existent completely.

And then it says, if you declare a local variable with value "nil", that local variable still shadows the global ones (if there is one), meaning a local variable (which its own should be an item of some table) exists after assigned "nil".

Why such conflict? What am I missing?

Thanks,

Dong