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@ --- what does it mean?

hey helpers out there I basically just want to know what the @ sign means what's the difference between doing this: @balance=0 and this balance=0 ?

Thank you! Marwan

3 Answers

The difference is that they have different "scope". A @ symbol is recognizable to your code throughout the whole instance of an object. Without the @ symbol the variable's scope becomes local to the code you declared it in.

def amethod
  local_variable = "This cannot be seen/accessed by the other method"
  @instance_variable = "This variable can be accessed by the other method"

def anothermethod
  local_variable = "Even with the same name as the local variable
 declared above, this one is totally different, and altering it won't affect the other."
  @instance_variable #this variable has the same value as the one above
Sergio Barrera
Sergio Barrera
4,198 Points

Instance variable --> @my_var (created as an instance of a class, it can be called outside it's method). local variable ----> my_var (for example, this variable is only valid inside a method. If you call it outside its method, you'll get an error.)

Thank you both! That cleared things up