修改属于扩展类的对象的默认返回值 [英] Modifying the default return value of an object belonging to an extended class

问题描述

我是rails语法相对较新。我有一个LogString类

  class LogString<数组
  

我用它做下面的操作

  logs = LogString.new 
 logs.push'this happened'
 logs.push'发生'
  pre> 
 
 
这很好。我想只能写入
  logs 
  
返回logs.join（'|'）
 
 
 
，所以我在寻找一个语法方法log_string here 
  class LogString<数组
 def log_string 
 self.join（'|'）
 end 
 end 
  
但是当我简单地写类实例名称时，log_string会自动调用：logs 
 
 
 
我该怎么办？
解决方案
你不能仅仅引用一个对象，并让它在对象上调用一个方法，但是你可以非常接近。 
 
 
 
如果您重写 to_s 方法（到字符串的缩写），您将能够
  class LogString<数组
 def to_s 
 self.join'| '
 end 
 end 
 
 log = LogString.new 
 log< message one
 log<< message two
 
 puts＃{log}
  
 
I am relatively new to the rails syntax. I have a LogString class
class LogString < Array
I do the following with it
logs = LogString.new
logs.push 'this happened'
logs.push 'that happened'
which works fine. i want to be able to just write only
logs
to return what would be logs.join( ' | ' )

so i am looking for a syntax something like the method log_string here
class LogString < Array
   def log_string
      self.join( ' | ' )
   end
end
but where log_string is automatically called when i simply write the class instance name: logs

how can i do that?
解决方案
You can't just reference an object and have it call a method on the object, but you can get pretty close.  

If you override the to_s method (short for "to string"), you'll be able to do something like...
class LogString < Array
  def to_s
     self.join ' | '
  end
end

log = LogString.new
log << "message one"
log << "message two"

puts "#{log}"


                        
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