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From: Grant Edwards <invalid@invalid.invalid>
Newsgroups: comp.lang.python
Subject: Re: What is a function parameter =[] for?
Date: Wed, 18 Nov 2015 22:33:11 +0000 (UTC)
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On 2015-11-18, Ian Kelly <ian.g.kelly@gmail.com> wrote:
> On Wed, Nov 18, 2015 at 2:08 PM, fl <rxjwg98@gmail.com> wrote:

>> def eList(val, list0=[]):

> The list0 parameter has a default value, which is [], an initially
> empty list. The default value is evaluated when the function is
> defined, not when it is called, so the same list object is used each
> time and changes to the list are consequently retained between calls.

One might consider this a way to have a local varible inside a
function that's "static" a-la C.  However, one probably oughtn't.

-- 
Grant Edwards               grant.b.edwards        Yow! Gibble, Gobble, we
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