[Python-Dev] Exception for setting attributes of built-in type (original) (raw)

Seo Sanghyeon sanxiyn at gmail.com
Sun Jun 14 21:09:25 CEST 2009


Exception for setting attributes of built-in type differs between CPython and IronPython. This is not purely theoretical, as zope.interface tries to set Implements declaration as implemented attribute of built-in type object, and excepts TypeError.

Python 2.6.1

object.flag = True TypeError: can't set attributes of built-in/extension type 'object'

IronPython 2.6

object.flag = True AttributeError: 'object' object has no attribute 'flag'

I was surprised that CPython raises TypeError. Library Reference seems to mention it here:

exception AttributeError Raised when an attribute reference or assignment fails. (When an object does not support attribute references or attribute assignments at all, TypeError is raised.) http://docs.python.org/library/exceptions.html

What does it mean that "an object does not support attribute references or attribute assignments at all"?

-- Seo Sanghyeon



More information about the Python-Dev mailing list