Falcolas wrote:
>> f = some_file() #maybe it's the file store for a database implementation
>> f.write('a bunch of stuff')
>> del f
>> #insert code that assumes f is closed.
>>
>> This is the sort of code that I warn against writing.
>>
>> f = some_file()
>> with f:
>> f.write("a bunch of stuff")
>> #insert code that assumes f is closed, but correctly this time
>>
>> is better.
>
> This has raised a few questions in my mind. So, here's my newbie
> question based off this.
>
> Is this:
>
> f = open(xyz)
> f.write("wheee")
> f.close()
> # Assume file is closed properly.
>
This will not immediately close f if f.write raises an exception since
the program stack is kept alive as a traceback.
> as "safe" as your code:
>
> f = some_file()
> with f:
> f.write("a bunch of stuff")
> #insert code that assumes f is closed, but correctly this time
>
The with statement is designed to be safer. It contains an implicit
try/finally that lets the file close itself in case of an exception.
--
Lenard Lindstrom
<[EMAIL PROTECTED]>
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