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[Python-Dev] Declaring setters with getters

Tony Lownds tony at PageDNA.com
Thu Nov 1 19:26:52 CET 2007 
On Nov 1, 2007, at 10:26 AM, glyph at divmod.com wrote:
> This is a minor nit, as with all decorators that take an argument,  
> it seems like it sets up a hard-to-debug error condition if you were  
> to accidentally forget it:
>
>   @property
>   def foo(): ...
>   @property.set
>   def foo(): ...
>
> would leave you with 'foo' pointing at something that wasn't a  
> descriptor at all.  Is there a way to make that more debuggable?

How about this: give the property instance a method that changes a  
property from read-only to read-write.
No parens, no frame magic. As a small bonus, the setter function would  
not have to be named the same as the
property.

class A(object):
   @property
   def foo(self):
     return 1

   @foo.setter
   def set_foo(self, value):
     print 'set:', value

-Tony
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