In Ruby, foo.inspect can print out all instance variables — can we print out an individual one if there is no accessor?

Question

Often, we can use p foo or foo.inspect to see the instance variables, but is it only the default behavior and the object can choose to show somethi

Answer 1

In Ruby, all access protection can be circumvented using reflection:

@bar.instance_variable_get(:@wah)

Answer 2

Trying to print a variable defined by attr_writer from outside the class will throw an error (undefined method 'wah' for #<Bar:0x0000...>) - but for debugging purposes you can use instance_variable_get as such:

b = Bar.new(:wah => "Hello")
b.wah # undefined method

b.instance_variable_get("@wah") # => "Hello"