ruby,attr-accessor , Using attr_accessor from inside class? [duplicate]

## Question:

Tag: ruby,attr-accessor

I'm trying to use an attr_accessor from inside the class where it is defined, to no avail. Why does this not work?

I would expect the following to output "new" in IRB:

irb(main):016:0> foo = StringClass.new
=> #<StringClass:0x2fbf2c0 @thing="old">
irb(main):017:0> foo.output
old
=> nil
irb(main):018:0> foo.change
=> "new"
irb(main):021:0> foo.output
old
=> nil


Here's the implementation:

class StringClass
def initialize
@thing = "old"
end

attr_accessor :thing

def output
puts thing
end

def change
thing = "new"
end
end


I can see that the thing= method is defined. I don't understand why that method is not being called when I try changing the value.

That is, because those methods should be called with self:

class StringClass
def initialize
@thing = "old"
end

attr_accessor :thing

def output
puts self.thing
end

def change
self.thing = "new"
end
end


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