Interview Questions and Answers

• Public, protected, and private.

• Public methods can be called by all objects and subclasses of the class in which they are defined in.

• Protected methods are only accessible to objects within the same class.

• Private methods are only accessible within the same instance.

• Be able to explain why this does (or doesn’t matter), and when you would want to set a method as private.

The ! indicates that the method is about to change the object itself.

Here’s an example:

foo = "A TEST STRING"  # a string called foo

foo.downcase!     # modifies foo permanently
a test string

puts foo          # prints modified foo
a test string

Similarly if you did not want the object to be changed you could have something simple like:

foo2 = "A 2nd Test String"  # a string called foo 

foo2.downcase     # modifies foo temporarily
a 2nd test string 

puts foo2 nbsp;    # prints original foo 
A 2nd Test String