ruby - 为什么 relative_require 在 Ruby 1.8.6 上不起作用？

Question

我正在 Windows 7 上学习 Ruby(使用版本 1.8.6)。

当我尝试运行下面的 stock_stats.rb 程序时，出现以下错误:

C:\Users\Will\Desktop\ruby>ruby stock_stats.rb
stock_stats.rb:1: undefined method `require_relative' for main:Object (NoMethodE
rror)

我有三个 v.small 代码文件:

stock_stats.rb

require_relative 'csv_reader'

reader = CsvReader.new

ARGV.each do |csv_file_name|
  STDERR.puts "Processing #{csv_file_name}"
  reader.read_in_csv_data(csv_file_name)
end

puts "Total value = #{reader.total_value_in_stock}"

csv_reader.rb

require 'csv' 
require_relative 'book_in_stock'

class CsvReader

  def initialize
    @books_in_stock = []
  end

  def read_in_csv_data(csv_file_name)
    CSV.foreach(csv_file_name, headers: true) do |row|
      @books_in_stock << BookInStock.new(row["ISBN"], row["Amount"])
    end
  end  

  # later we'll see how to use inject to sum a collection
  def total_value_in_stock
    sum = 0.0        
    @books_in_stock.each {|book| sum += book.price}
    sum
  end  

  def number_of_each_isbn
    # ...
  end

end       

book_in_stock.rb

require 'csv' 
require_relative 'book_in_stock'

class CsvReader

  def initialize
    @books_in_stock = []
  end

  def read_in_csv_data(csv_file_name)
    CSV.foreach(csv_file_name, headers: true) do |row|
      @books_in_stock << BookInStock.new(row["ISBN"], row["Amount"])
    end
  end  

  # later we'll see how to use inject to sum a collection
  def total_value_in_stock
    sum = 0.0        
    @books_in_stock.each {|book| sum += book.price}
    sum
  end  

  def number_of_each_isbn
    # ...
  end

end       

在此先感谢您的帮助。

Answer 1

require_relative 在您的 Ruby 版本中不存在。您可以升级 Ruby，安装 backports gem 和 require 'backports/1.9.1/kernel/require/relative' 但最简单的解决方法是将您的 require 更改为:

require File.join(File.dirname(__FILE__), 'csv_reader')