class Document
attr_reader :title, :text
attr_accessor :formatter
def initialize(formatter)
@title = 'Document'
@text = ['Things are going', ' well.']
@formatter = formatter
end
def output_report
@formatter.output_report(self)
end
end
class Formatter
def output_report(context)
raise 'Abstract method called'
end
end
class HTMLFormatter < Formatter
def output_report(context)
puts('<html>')
puts(' <head>')
puts(" <title>#{context.title}</title>")
puts(' </head>')
puts(' <body>')
context.text.each do |line|
puts(" <p>#{line}</p>")
end
puts(' </body>')
puts('</html>')
end
end
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