[Python-bugs-list] [ python-Bugs-575773 ] Negative __len__ provokes SystemError

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Thu, 25 Jul 2002 09:06:42 -0700


Bugs item #575773, was opened at 2002-06-30 22:27
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Category: Python Interpreter Core
Group: None
>Status: Closed
>Resolution: Fixed
Priority: 5
Submitted By: Tony Lownds (tonylownds)
>Assigned to: Jeremy Hylton (jhylton)
Summary: Negative __len__ provokes SystemError

Initial Comment:
class A(object):
  def __len__(self): 
    return -2  # anything < 0

  def __getslice__(self, x, y):  
    pass

A()[-1:]   # anything < 0

... results in....

Traceback (most recent call last):
  File "cause_system_error.py", line 8, in ?
    A()[-1:]   # anything < 0
SystemError: error return without exception set




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>Comment By: Jeremy Hylton (jhylton)
Date: 2002-07-25 16:06

Message:
Logged In: YES 
user_id=31392

Fixed in rev 2.162 of typeobject.c.


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https://sourceforge.net/tracker/?func=detail&atid=105470&aid=575773&group_id=5470