@ --- what does it mean?

Question

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

Answer 1 · 2014-01-19T05:06:41Z

January 19, 2014 5:06am

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"
end

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
end

Answer 2 · 2014-01-19T07:02:10Z

January 19, 2014 7:02am

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.)

Answer 3 · 2014-01-19T14:30:23Z

January 19, 2014 2:30pm

Thank you both! That cleared things up

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Marwan Sulaiman

Marwan Sulaiman

@ --- what does it mean?

3 Answers

alex harrison

alex harrison

Sergio Barrera

Sergio Barrera

Marwan Sulaiman

Marwan Sulaiman