[Python-Dev] With statement

[Michael Hudson]

Oren Tirosh <oren-py-d@hishome.net> writes:

> Let's assume that a new 'local' statement is added to Python. At the end 
> of the current block the __del__ method of any references declared local 
> is guaranteed to be called. The object must have exactly one remaining 
> reference, otherwise an exception is raised. In a GC implementation it may 
> make some change to the object so that any remaining references to it 
> become stale references and raise an exception as soon as they are touched 
> in any way. Note that a reference to a closed file object is already a 
> stale reference and raises an exception if any I/O operation is attempted 
> on it.

Two comments:

1) The resource-allocation-is-initialization pattern works very well
   in C++, but I'm unconvinced that we should aim to copy it exactly
   -- it's a nice solution to the problem, but not the only possible
   or best one, IMHO.

2) Without the ability to define a scope at will, RAiI becomes less useful.

Cheers,
M.

-- 
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