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| Subject | Re: lazy properties? |
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| From | "Stefan H. Holek" <stefan@epy.co.at> |
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| Date | Fri, 2 Nov 2012 09:36:11 +0100 |
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| To | Andrea Crotti <andrea.crotti.0@gmail.com> |
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On 01.11.2012, at 22:38, Andrea Crotti wrote: > Seeing the wonderful "lazy val" in Scala I thought that I should try to get the following also in Python. > The problem is that I often have this pattern in my code: > > class Sample: > def __init__(self): > self._var = None > > @property > def var(self): > if self._var is None: > self._var = long_computation() > else: > return self._var > > > which is quite useful when you have some expensive attribute to compute that is not going to change. > I was trying to generalize it in a @lazy_property but my attempts so far failed, any help on how I could do that? There is a ready made and well tested lazy decorator at http://pypi.python.org/pypi/lazy Stefan -- Stefan H. Holek stefan@epy.co.at
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Re: lazy properties? "Stefan H. Holek" <stefan@epy.co.at> - 2012-11-02 09:36 +0100
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