# File lib/spreadsheet/datatypes.rb, line 21 def boolean *args args.each do |key| define_method key do name = "@#{key}" !!(instance_variable_get(name) if instance_variables.include?(name)) end define_method "#{key}?" do send key end define_method "#{key}=" do |arg| arg = false if arg == 0 instance_variable_set("@#{key}", !!arg) end define_method "#{key}!" do send "#{key}=", true end end end