Question

I have an hash consisting of:

flow = ["a", "b", "c"]
h = [{"case_id"=>1, "a"=>{"x"=>"text", "option"=>"..." },"b"=>{"report"=>"text", "option"=>"..." } ,"c"=>{"y"=>"text", "option"=>"..." }},{"case_id"=>2, "a"=>{"x"=>"text", "option"=>"..." },"b"=>{"report"=>"text", "option"=>"..." } ,"c"=>{"y"=>"text", "option"=>"..." }}]
@case = 0
@report = ""
flow.each do |step|
  if h[@case][step]['report']
    @report = h[@case][step]['report']
  end
end

the console gives me the following error:

NoMethodError in MainController#index
undefined method `[]' for nil:NilClass

Why?! In a previous program, but using ruby 187, gave no problem. But now, with ruby ​​193, gives this error.

Answer 1

flow = ["a", "b", "c"]
h = { "a"=>{"x"=>"text", "option"=>"..." },"b"=>{"report"=>"text", "option"=>"..." } ,"c"=>{"y"=>"text", "option"=>"..." }}
flow.each do |f|
  if h[f]['report']
    #something
  end
end

Ruby has some great iteration helper provided by enumeration class

http://www.ruby-doc.org/core-1.9.3/Array.html#method-i-each