2008/8/20 Patrick Li [email protected]:
I noticed this this afternoon:
Unmarshaling a marshaled object, makes all dynamically created methods
Patrick, that’s not correct. Classes and methods aren’t changed upon
#Here’s a class that dynamically creates the method MyPage#print()
This creates a MyPage#print method for all MyPage instances as soon
as the first instance is created.
#Test the class
page = MyPage.new
Here the MyPage#print method is created.
page.print #prints nil
#Marshal the object
File.open(“object.obj”,“w”) do |f|
Maybe you should stop Ruby at this point, see below. If you just
continue with the following code, you don’t get the output you’ve
shown, as botp already wrote.
#UnMarshal the object, and try printing again
page = nil
File.open(“object.obj”,“r”) do |f|
page = Marshal.load(f)
#private method `print’ called for #<MyPage:0x27af394 @a=3>
No, you don’t get this error. See botp’s example.
If you stop Ruby at the point shown above, then start a new session,
define the MyPage class as above, and then run the unmarshalling code,
then it’s normal and expected that you get a NoMethodError.
Unmarshaling an object doesn’t call it’s class’ #initialize method, so
the new method MyPage#print never is defined in the second Ruby
session. That’s why you are calling the private method Kernel#print
and get the error.