How do I convert the following to a clear one-liner in ruby?
def questions
results = []
sections.each do |section|
results = results.concat(Question.find_all_by_survey_section_id(section.id))
end
results
end
I feel like I could use the &: (Symbol#to_proc) and returning methods in there somehow.
Assuming that SurveySection has_many :questions, you can simplify this to:
sections.map(&:questions).flatten
Or if the method is defined in an ActiveRecord model, you could just declare that it has_many :questions, :through => :sections and you won't have to define the method at all.
def questions
sections.map do |section|
Question.find_all_by_survey_section_id(section.id)
end.flatten
end
or
def questions
sections.inject([]) do |all, section|
all.concat Question.find_all_by_survey_section_id(section.id)
end
end
You can use map or collect, like so
def questions
sections.map{|section| Question.find_all_by_survey_section_id(section.id)}.flatten
end
However, I dont think you can use symbol to proc for this because you are not just calling a method on the collection.
Without a block in sight:
def questions
sections.map(&:id).flat_map(&Question.method(:find_all_by_survey_section_id))
end
