Ruby中类的未定义方法

Question

I'm creating a class. I'm pulling data from a hash named ROLL_CALL . The all method should return an array of Team objects.

require_relative "./team_data"
class Team
  attr_reader :name
  def intialize (name)
    @name = name
    def all
      all_teams = []
      TeamData::ROLL_CALL.each do |team, info|
        all_teams << Team.new(team)
      end
      all_teams
    end
  end
end

When I try to call Team.all , I get the undefined method for all .

Answer 1

Your code isn't structured correctly. That def all should be at the top-level and declared as a class-style method. There's also some other things worth fixing:

require_relative "./team_data"

class Team
  def self.all
    TeamData::ROLL_CALL.map do |team, info|
      Team.new(team)
    end
  end

  attr_reader :name

  def intialize (name)
    @name = name
  end
end

Use map instead of creating a temporary array and jamming things into it with each only to return it in the end, as that's exactly what map does for you.