Ruby

Feature #16783

Updated by koriroys (Kori Roys) about 5 years ago

I recently ran into this case while trying to explain why `self` is needed for calling setters (can't disambiguate between creating a local variable versus calling the setter because of the syntactic sugar). However, I couldn't come up with a good reason why `self` throws an error when calling private getters. It feels inconsistent? I think it would be more consistent to be able to specify `self.private_getter` and `self.private_setter = "value"`, though I don't know the implications. Would this be possible? Would people appreciate this? 

 ``` ruby 
 class Thing 

   # works 
   def public_method_calling_private_setter_with_explicit_self 
     self.name = "value" 
   end 
  
   # works, but doesn't call the private setter 
   # common beginner mistake 
   def public_method_creating_local_variable 
     name = "whoops!" 
   end 
  
   # works 
   def public_getter_accessing_instance_variable 
     @name 
   end 
  
   # works 
   def public_getter_calling_private_getter_with_implicit_self 
     private_name 
   end 

   # DOES NOT work 
   def public_getter_calling_private_getter_with_explicit_self 
     self.private_name 
   end 

   private 
   def name=(value) 
     @name = value 
   end 
  
   def private_name 
     @name 
   end 
 end 

 thing = Thing.new 
 thing.public_getter_accessing_instance_variable #=> nil 
 thing.public_method_calling_private_setter_with_explicit_self # => "value" 
 thing.public_getter_accessing_instance_variable #=> "value" 

 thing.public_method_creating_local_variable # => "whoops!" 
 # instance variable unchanged 
 thing.public_getter_accessing_instance_variable # => "value" 

 thing.public_getter_calling_private_getter_with_implicit_self # => "value" 

 # this following method should this work? work 
 thing.public_getter_calling_private_getter_with_explicit_self # => NoMethodError (private method `private_name' called for Thing) Thing4) 
 ``` 

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