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an Exception base-class that supports keyword arguments and pretty printing

Python, 41 lines
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class ExceptionContainer(Exception):
    def __init__(self, message = "", **kw):
        self.__dict__["__info"] = Container(message = message, **kw)
    def __delattr__(self, name):
        delattr(self.__dict__["__info"], name)
    def __getattr__(self, name):
        return getattr(self.__dict__["__info"], name)
    def __setattr__(self, name, value):
        setattr(self.__dict__["__info"], name, value)
    def __repr__(self):
        return repr(self.__dict__["__info"])
    def __str__(self):
        return str(self.__dict__["__info"])

---------
example:
---------
>>> class FileNotFoundError(ExceptionContainer):
...     pass
...
>>> raise FileNotFoundError("failed to open the file!", filename = "/tmp/blah", errno = 17)
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
__main__.FileNotFoundError: Container:
    errno = 17
    filename = '/tmp/blah'
    message = 'failed to open the file!'
>>>
>>> try:
...     raise FileNotFoundError("failed to open the file!", filename = "/tmp/blah", errno = 17)
... except FileNotFoundError, ex:
...     ex.errno = 18
...     raise
...
Traceback (most recent call last):
  File "<stdin>", line 2, in ?
__main__.FileNotFoundError: Container:
    errno = 18
    filename = '/tmp/blah'
    message = 'failed to open the file!'
>>>

!! requires the Conatiner class from my Container's recipe !!

finally, you can throw exceptions with keyword arguments. no more ugly tuple unpacking.

3 comments

Ori Peleg 17 years, 11 months ago  # | flag

cool! I love it.

tomer filiba (author) 17 years, 11 months ago  # | flag
Christopher Dunn 17 years, 10 months ago  # | flag

Wrong category. Interesting, but this is in the wrong category. "Extending" refers to loading symbols into the Python interpretter, via either a dynamic library or recompiling the interpretter itself.

Extending the Exception class would go under "Object Oriented", maybe.

Created by tomer filiba on Sat, 13 May 2006 (PSF)
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