Question

在练习19中的学习Ruby Hard The Way> 一书中，它说应该采用所提供的功能：

def cheese_and_crackers(cheese_count, boxes_of_crackers)
  puts "You have #{cheese_count} cheeses!"
  puts "You have #{boxes_of_crackers} boxes of crackers!"
  puts "Man that's enough for a party!"
  puts "Get a blanket.\n"
end

并探索不同的方法。我试着探索函数的参数并用它写一个文本：

file = ARGV.first

puts "Let's make a test?"
puts "Does the output file exist? #{File.exist?(arquivo)} "
puts "Ready, hit RETURN to continue, CTRL-C to abort."

$stdin.gets

def success(price, recipe)
  puts """Text goes on like this:
  In order to become a coder, You must dedicate yourself.\n
  For that, you must pay a price, such as #{price}\n
  Becoming a coder also requires #{recipe}\n"""
end

puts "What is the price to pay in order to become a coder?"
price = $stdin.gets
puts "What are the fundamental components in order to become a coder?"
recipe = $stdin.gets

coder = success(price, recipe)

motivational = File.open(file, 'w')
motivational.write(coder)

puts "Read this every day."

但我似乎无法让它将函数写入新的test.txt文件中。 test.txt文件为空。

Answer 1

调用puts时，您正在写入stdout，但返回值将为空。

改变这个：

def success(price, recipe)
  return """Text goes on like this:
  In order to become a coder, You must dedicate yourself.\n
  For that, you must pay a price, such as #{price}\n
  Becoming a coder also requires #{recipe}\n"""
end

然后：

motivational.close()

编辑：这是一个扩展的解释：当调用puts时，你只是将字符串写入stdout，这是程序的默认输出。方法（函数）可以具有返回值。对于success方法，您需要返回字符串，以便将其写入文件中。如果您拨打puts而不是return，success方法将不会返回任何值，因此请将文件留空。

对于close()调用，建议在脚本结束前关闭文件流。

请查看这些参考资料以获取更多信息：

https://www.ruby-lang.org/en/documentation/quickstart/2/

http://ruby-doc.org/core-2.2.3/IO.html

在Ruby上编写带有已定义函数的新文件

1 个答案: