Question

为什么程序在命令行中执行后退出？

我将下面的代码保存为.rb文件。当我运行它时，它会遍历所有内容，但它不会向我显示我想要查看的结果哈希。相反，程序退出。

    def create_list
    print "What is the list name? "
    name=gets.chomp

    hash={"name"=>name,"items"=>Array.new}
    return hash
    end

    def add_list_item
    print "What is the item called? "
    item_name=gets.chomp

    print "How much? "
    quantity=gets.chomp.to_i

    hash={"name"=>item_name, "quantity"=>quantity}
    return hash
    end


   def print_separator(character="-")
    puts character *80

    end


   def print_list(list)
     puts "List: #{list['name']}"
     print_separator()

   list["items"].each do |item|
   puts "\tItem: " + item['name'] + "\t\t\t" +
   "Quantity: " + item['quantity'].to_s

   end
    print_separator()

    end

   list=create_list()
   list['items'].push(add_list_item())
   list['items'].push(add_list_item())

   puts "Here is your list: \n"
   print_list(list)

Answer 1

我看了你的代码，我建议当你遇到这种问题时运行命令ruby -wc file_name.rb，这就是打印出来的：

list.rb:22: warning: *' after local variable or literal is interpreted as binary operator

list.rb:22: warning: even though it seems like argument prefix

list.rb:24: warning: mismatched indentations at 'end' with 'def' at 21

list.rb:38: warning: mismatched indentations at 'end' with 'def' at 27

Syntax OK

因此，在修复缩进之后，您需要解决的下一件事是print_separator方法：

def print_separator(character="-")
     puts character *80
end

将其更改为：

def print_separator()
    80.times do |n|
      print "-"
    end
    puts
end

这也是相同代码的工作版本：

def create_list
  print "What is the list name? "
  name=gets.chomp

  hash={"name"=>name,"items"=>Array.new}
  return hash
end

def add_list_item
  print "What is the item called? "
  item_name=gets.chomp

  print "How much? "
  quantity=gets.chomp.to_i

  hash={"name"=>item_name, "quantity"=>quantity}
  return hash
end


def print_separator()
    80.times do |n|
       print "-"
    end
    puts
end


def print_list(list)
  puts "List: #{list['name']}"
  print_separator()

  list["items"].each do |item|
    puts "\tItem: " + item['name'] + "\t\t\t" +
    "Quantity: " + item['quantity'].to_s
  end
  print_separator()
end

list=create_list()
list['items'].push(add_list_item())
list['items'].push(add_list_item())

puts "Here is your list: \n"
print_list(list)

输出：

What is the list name? My list
What is the item called? apple
How much? 2
What is the item called? orange
How much? 2
Here is your list:
List: My list --------------------------------------------------------------------------------
Item: apple Quantity: 2
Item: orange Quantity: 2
--------------------------------------------------------------------------------

在命令提示符中执行代码后Ruby程序退出

1 个答案: