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Date: Fri, 10 Jan 2014 09:38:27 -0800 (PST)
From: Albert-Jan Roskam <fomcl@yahoo.com>
Subject: L[:]
To: Python <python-list@python.org>
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Xref: csiph.com comp.lang.python:63666

In Python Cookbook, one of the authors (I forgot who) consistently used the=
 "L[:]" idiom like below. If the second line simply starts with "L =3D" (so=
 no "[:]") only the name "L" would be rebound, not the underlying object. T=
hat was the author=C5=9B explanation as far as I can remember. I do not get=
 that. Why is the "L[:]" idiom more memory-efficient here? How could the in=
creased efficiency be demonstrated?

#Python 2.7.3 (default, Sep 26 2013, 16:38:10) [GCC 4.7.2] on linux2
>>> L =3D [x ** 2 for x in range(10)]
>>> L[:] =3D ["foo_" + str(x) for x in L]


Thanks!


Regards,

Albert-Jan



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All right, but apart from the sanitation, the medicine, education, wine, pu=
blic order, irrigation, roads, a=20

fresh water system, and public health, what have the Romans ever done for u=
s?

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