Ruby on Rails "uninitialized constant" error -

i creating application tracks customers quotes. customer has many quotes , 1 belongs 1 customer. trying use method combines first name , last name fields produce full name. code follows.

customer model:

class customer < activerecord::base   has_many :quotes   def full_name     "#{fname} #{lname}"   end end 

quotes form.html.erb

<div class="field">   <%= f.label :customer_name %><br>   <%= collection_select :quote, :customer_id, customer.all, :id, :full_name, {}, {:multiple => true} %>   </div> 

when try create new record, given "uninitialized constant customer::fname" error. please advise?

in ruby identifier begins uppercase letter constant.

irb(main):001:0> foo = 'bar' => "bar" irb(main):002:0> foo = 'baz' (irb):2: warning: initialized constant foo (irb):1: warning: previous definition of foo here => "baz" irb(main):003:0>  

so class names constants written in camelcase (ghostwriter) , attributes , methods commonly written in snake_case.

actual constants written uppercase.

so bring together

class square # class name square constant   sides = 4 # constant    attr_accessor :height    attr_accessor :width   attr_accessor :background_color # attributes written in snakecase    def area      @height * width   end    def get_point # method names.   end  end