Directly accessing an instance variable vs. Using an accessor method

ruby instance-variables accessor
pistacchio picture pistacchio · Jan 9, 2011 · Viewed 11.5k times · Source

Can anyone explain the difference between accessing an instance attribute via self.attribute and by @attribute?

Answer

sepp2k picture sepp2k · Jan 9, 2011

self.attribute calls the method attribute.
self.attribute = value calls the method attribute= with the argument value.
@attribute and @attribute = value get/set the value of the instance variable @attribute.

So basically they're two entirely different things.

However if you call attr_accessor :attribute it defines the method attribute to return @attribute and the method attribute=(value) to set @attribute = value. So in that case, there is no difference.

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