Hi all,
I'm using simple classes as a container of named values and I'm
instantiating a lot of them in a very short time.
i was wondering if there is any benefit in using dicts instead from a
performance/memory usage point of view?
regards,
Guyon Morée http://gumuz.looze.net
Jul 25 '06
12  1436 
>Guido sez:
>
__slots__ is a terrible hack with nasty, hard-to-fathom side
effects that should only be used by programmers at grandmaster and
wizard levels. Unfortunately it has gained an enormous undeserved
popularity amongst the novices and apprentices, who should know
better than to use this magic incantation casually.
But, if they are novices, why should they be expected to know better?
I just re-read http://docs.python.org/ref/slots.html#l2h-217 and don't
see anyplace where it says, "Warning: for use by wizards only".
Don't optimize prematurely. Write whatever is cleaner, simpler and
makes more sense. Such that if someone (or even yourself) looks at it
10 years from now they'll know exactly what is going on. As far as
what is slower or what functionality you will use and what you won't --
well, if you won't use it then why worry about it and to find out if it
is slower run a quick benchmark and you'll know...
-NickV be************@ lycos.com wrote:
Simon Hibbs:
It seems to me that unless you
need some of the functionality supplied with dictionaries (len(a),
has_key, etc) then simple objects are a syntacticaly cleaner and more
natural way to express yourself.
I'd say the opposite. Classes contain a dict of their attributes, etc.
So if you don't need the functionality supplied by objects, then using
simpler dictionaries is better. (But in the end the choice has to be
made according to the specific situations).
Bye,
bearophile
In article <ea**********@r eader2.panix.co m>, Roy Smith <ro*@panix.comw rote:
>>Guido sez:
__slots__ is a terrible hack with nasty, hard-to-fathom side
effects that should only be used by programmers at grandmaster and
wizard levels. Unfortunately it has gained an enormous undeserved
popularity amongst the novices and apprentices, who should know
better than to use this magic incantation casually.
But, if they are novices, why should they be expected to know better?
I just re-read http://docs.python.org/ref/slots.html#l2h-217 and don't
see anyplace where it says, "Warning: for use by wizards only".
Unfortunately, the Python docs are currently suboptimal when it comes to
new-style classes.
--
Aahz (aa**@pythoncra ft.com) <* http://www.pythoncraft.com/
"Debugging is twice as hard as writing the code in the first place.
Therefore, if you write the code as cleverly as possible, you are, by
definition, not smart enough to debug it." --Brian W. Kernighan This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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