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jaberwacky

Question about using const.

6 posts in this topic

If I use const alone to declare a variable in a func there seems to be some behavior I don't quite understand.

When the variable is declared globally then this error is thrown: "error: $my_var previously defined as a non-'Const' var."   So it appears to check the global scope first.  Seems like it should check local first, right?

Global $my_var = "Hello World"

_my_func()

Func _my_func()
  Const $my_var = "Good Bye World" ; error: $my_var previously defined as a non-'Const' var.
EndFunc

Then this snippet makes it seem to me that the local scope is checked rather than global.

_my_func()

ConsoleWrite($my_var & @CRLF) ; warning: $my_var: possibly used before declaration.

Func _my_func()
  Const $my_var = "Good Bye World"
EndFunc

Is this all correct?

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Because the variable $my_var has a Global scope. If you need to re-use the same name in your function set the scope by using

Local Const $my_var = "Good by World!"

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The errors are correct. Const doesn't define/re-define scope.

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Updated: 04/09/2015

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OK, I can understand that now.  Thanks.

No problem. It's an easy mistake to make. At least you're using this keyword.


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Updated: 04/09/2015

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I love using const and use it all the time.  It makes it easier for me to understand my code but supposedly makes it somewhat (ever so slightly?) slower which is a trade off I'm willing to make.

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