lib/validation/condition.rb
def MEMBER_OF(list, *lists)
      lists = [list, *lists]
      unless lists.all?{|l|l.respond_to? :all?}
        raise TypeError, 'list must respond #all?'
      end

      ->v{
        lists.all?{|l|l.include? v}
      }
    end
def MEMBER_OF(list, *lists)
      lists = [list, *lists]
      unless lists.all?{|l|l.respond_to? :all?}
        raise TypeError, 'list must respond #all?'
      end

      ->v{
        lists.all?{|l|l.include? v}
      }
    end
def MEMBER_OF ( list , * lists ) lists = [ list , lists ] unless lists . all? { | l | l . respond_to? :all? } raise TypeError , 'list must respond #all?' end -> v { lists . all? { | l | l . include? v } } end
A condition builder.
 @param list [#all?]
 @param lists [#all?]
 @return [lambda]
   this lambda return true
   if all lists including the object
A condition builder .