Copyright © 2015-2016
Robert W. Hasker

Note 4: Classier Ruby

• Keeping code readable
  • What does this or this do?
  • With tabs
  • indented, but still unreadable - what's wrong?
  • Added spaces
  • Final version
  (see here for the original versions)

• Instance, class methods:

            class Task
              # @description: string
              # @duration:    integer minutes
              attr_accessor :description, :duration
  
              @@task_count = 0
  
              # initalize: string X string
              def initialize(description, duration)
                @description = description
                @duration    = duration
                @@task_count = @@task_count + 1
              end
  
              # scale: double -> void
              def scale(amount)
                @duration *= amount
              end
  
              # to_s: void -> void
              def to_s
                "#{@description} for #{duration} minutes"
              end
  
              # -> int
              def self.tasks_created
                @@task_count
              end
            end
  

• Notes on styles:
  • Two space indents - try it, you'll like it
  • Avoid abbreviating class variables
  • Capitalization standards:
    • CamelCase class names
    • snake_case variables/attributes/methods
    • all caps for constant values
  • .map, .each, .select, not loops
  • use symbols for internal values:

            if color == :red
    

  • and drop then, don't add unnecessary ()s on if
  • strive for readable code:

            numbers.clear() if numbers.size > 50