Example of Ruby OOP

driver.rb

require "person.rb"

person = Person.new({firstname: 'john', lastname: 'doe'})
puts person.firstname # john
puts person.lastname  # doe

# in php it would be person->getFullname();
puts person.fullname  # Mr. john doe

# in php its person->setFullname();
person.fullname = "Abe Lincoln" # NoMethodError: undefined method `fullname=' <= this is a setter
person.prefix                   # NoMethodError: private method `prefix' called for #<Person:0x007fc74d949af0>

# MORE INFO
#
# Person#methods: firstname  firstname=  fullname  lastname  lastname=
# instance variables: @firstname  @fullname  @lastname

person.rb

class Person
  # Attr_accessor creates instance variables for the class instance 
  # (i.e. @name, etc).
  # AND creates GETTERS and SETTERS for all listed attributes (by the same name as the attribute)
  attr_accessor :firstname, :lastname
  
  # Attr_reader creates @fullname AND a getter ONLY
  attr_reader :fullname
  
   #this is equivalent to __construc()
  def initialize(params)
  	@name = params[:firstname]
  	@lastname = params[:lastname]
  	@fullname = fullname
  end
  
  def fullname
    # in php this would be:
    # return _prefix() . " " . getFirstname() . " " . getLastname();
    return "#{prefix} #{firstname} #{lastname}"
  end
  
  private
  #everything after this is private
  def prefix
    return "Mr."
  end
end

Notes

• Person has getters and setters by same name as the attribute for firstname and lastname
• Person has only a getter (fullname) for fullname. in php it would be Person->getFullname();
• Person.fullname = "junk" throws error bc there's no setter defined.