The function(s) defined within a function works fine with any hierarchy only within the main object but gives NoMethodError inside a class.

Lets exemplify it!

Here are the example of both main object and inside a class…

<br /> def person<br /> def author<br /> p “I am author”<br /> end<br /> def reader<br /> p “I am reader”<br /> end<br /> def publisher<br /> def authorized<br /> p “I am a authorized publisher”<br /> end<br /> end<br /> end</p> <p> person.author # => I am author<br /> person.reader # => I am reader<br /> person.publisher.authorized # => I am authorized publisher</p> <p> class Person<br /> def publisher<br /> def authorized<br /> p “I am a authorized publisher”<br /> end<br /> end<br /> end</p> <p> Person.new.publisher.authorized # => NoMethodError<br />

Its an unexpected behavior in the main object. I don’t know whether its a bug or the feature. But as Matz says it will be removed in the future version of ruby, might be in 2.0