mrkafk at gmail.com
Wed Mar 3 22:11:40 CET 2010
Arnaud Delobelle wrote:
> mk <mrkafk at gmail.com> writes:
>> All of Python’s immutable built-in objects are hashable, while no
>> mutable containers (such as lists or dictionaries) are.
>> Well ok, hashable they're not; but apparently at least dict and list
>> have id()?
> lists and dicts are not hashable, but their types are:
> So just use the type as the key to the dictionary you maintain in your
Hmm I have tested it and it seems to work.
> But the question is what you use your singleton for.
Well, partly this was for sake of learning; but partially I was thinking
whether singleton as such may be useful for implementing "global queue
of tasks" for worker threads in a large program: instead of handing down
over and over the same reference to the global queue of tasks, classes
or functions could call Singleton() and be done with it.
Or I could make my life simpler and use global variable. :-)
I will soon need to write such program, with remote calls from pyro
(most probably), many worker threads, short-running jobs and
long-running jobs, etc.
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