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Programming in Lua | ![]() |
Part I. The Language Chapter 1. Getting Started |
Global variables do not need declarations. You simply assign a value to a global variable to create it. It is not an error to access a non-initialized variable; you just get the special value nil as the result:
print(b) --> nil b = 10 print(b) --> 10
Usually you do not need to delete global variables; if your variable is going to have a short life, you should use a local variable. But, if you need to delete a global variable, just assign nil to it:
b = nil print(b) --> nilAfter that, it is as if the variable had never been used. In other words, a global variable is existent if (and only if) it has a non-nil value.
Copyright © 2003-2004 Roberto Ierusalimschy. All rights reserved. |
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