Как так?

rails console

irb(main):001:0> require './app/example_user.rb'
=> true
irb(main):003:0> example = User.new
=> #<User:0x0055f1cf956f20 @name=nil, @email=nil>
 
irb(main):004:0> example.name='Rijen'
=> "Rijen"
irb(main):005:0> example
=> #<User:0x0055f1cf956f20 @name=nil, @email=nil>
irb(main):006:0> example.name
=> "Rijen"
irb(main):008:0> example.email = 's.rijen@ya.ru'
=> "s.rijen@ya.ru"
        
irb(main):009:0> example.formatted_email
=> "Rijen <s.rijen@ya.ru>"

irb(main):011:0> u = User.new(name:'Vasya Pupkin',email:'v.pupkin@dom.com')
=> #<User:0x0055f1d2837498 @name="Vasya Pupkin", @email="v.pupkin@dom.com">
irb(main):012:0> u
=> #<User:0x0055f1d2837498 @name="Vasya Pupkin", @email="v.pupkin@dom.com">
irb(main):013:0> u.formatted_email
=> "Rijen <s.rijen@ya.ru>"
irb(main):015:0> u.name
=> "Rijen"
irb(main):016:0> u
=> #<User:0x0055f1d2837498 @name="Vasya Pupkin", @email="v.pupkin@dom.com">
irb(main):017:0> u.name
=> "Rijen"