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Re: Use and usefulness of the as syntax

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On 11/12/11 05:56, candide wrote:
> First, could you confirm the following syntax
>
> import foo as f
>
> equivalent to
>
> import foo
> f = foo

and the issuing "del foo"


> Now, I was wondering about the usefulness in everyday programming of the
> as syntax within an import statement. Here are some instances retrieved
> from real code of such a syntax
>
> import numpy as np
> import math as _math
> import pickle as pickle
>
> -- In the last case, I can see no point

Without context, I'm guessing the last one is merely keeping 
parity in a block that reads:

   try:
     import cPickle as pickle
   except ImportError:
     import pickle as pickle



> So what is the pragmatics of the as syntax ?

The most common use-case I see is your first:  to shorten a 
frequently-used namespace.  I do this frequently with

   import Tkinter as tk

which makes it obvious where things are coming from.  I hate 
trying to track down variable-names if one did something like

   from Tkinter import *


The second big use case I see regularly is the full example 
(above):  try to import a faster/native module that shares an 
interface with a pure-python implementation.  However in the 
above, the "import pickle as pickle" is a uselessly redundant.

-tkc

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Use and usefulness of the as syntax candide <candide@free.invalid> - 2011-11-12 12:56 +0100
  Re: Use and usefulness of the as syntax Chris Angelico <rosuav@gmail.com> - 2011-11-12 23:27 +1100
  Re: Use and usefulness of the as syntax Arnaud Delobelle <arnodel@gmail.com> - 2011-11-12 12:29 +0000
    Re: Use and usefulness of the as syntax candide <candide@free.invalid> - 2011-11-17 16:48 +0100
      Re: Use and usefulness of the as syntax alex23 <wuwei23@gmail.com> - 2011-11-17 18:38 -0800
  Re: Use and usefulness of the as syntax Tim Chase <python.list@tim.thechases.com> - 2011-11-12 06:43 -0600
  Re: Use and usefulness of the as syntax Rafael Durán Castañeda <rafadurancastaneda@gmail.com> - 2011-11-12 13:48 +0100
    Re: Use and usefulness of the as syntax 0xfn <oleg.rimko@gmail.com> - 2011-11-13 00:55 -0800
      Re: Use and usefulness of the as syntax Terry Reedy <tjreedy@udel.edu> - 2011-11-13 17:16 -0500
  Re: Use and usefulness of the as syntax Tim Wintle <tim.wintle@teamrubber.com> - 2011-11-12 13:03 +0000
  Re: Use and usefulness of the as syntax Mel Wilson <mwilson@the-wire.com> - 2011-11-12 08:59 -0500
  Re: Use and usefulness of the as syntax candide <candide@free.invalid> - 2011-11-17 16:48 +0100

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