Nils Oliver Kröger <[EMAIL PROTECTED]> writes:
> If you want to "reuse" the file, you will have to delete your classes
> instance explicitly using the del statement ... this will also call
> the destructor.
Sometimes, but not always. The `del' statement simple removes the
reference to the instance and decrements its reference count. The
__del__() routine for the instance still only gets called whenever the
object is actually garbage collected. Furthermore, the Python Reference
Manual notes that:
Circular references which are garbage are detected when the option
cycle detector is enabled (it's on by default), but can only be
cleaned up if there are no Python-level __del__() methods involved.
[http://docs.python.org/ref/customization.html]
The proper way to handle the case presented by the OP is for the class
to expose a close()-like method and/or -- for use with Python 2.5 and
later -- implement the methods of the context manager protocol
[http://docs.python.org/ref/context-managers.html]. The following code
supports basic usage:
def close(self):
self._file.close()
print "File closed"
def __enter__(self):
return self
def __exit__(self, *exc_info):
self.close()
return False
Then the users of this class can freely do any of:
f = fout(filename)
...
f.close()
with fout(filename) as f:
...
with closing(fout(filename)) as f:
...
HTH,
-Marshall
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