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Date: Fri, 17 Feb 2012 08:00:54 +0000
Subject: Re: question about function pointer
From: Arnaud Delobelle <arnodel@gmail.com>
To: Zheng Li <dllizheng@gmail.com>
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On 17 February 2012 07:53, Zheng Li <dllizheng@gmail.com> wrote:
> def method1(a =3D None):
> =C2=A0 =C2=A0 =C2=A0 =C2=A0print a
>
> i can call it by
> method1(*(), **{'a' : 1})
>
> I am just curious why it works and how it works?
> and what do *() and **{'a' : 1} mean?
>
> when I type *() in python shell, error below happens
>
> =C2=A0File "<stdin>", line 1
> =C2=A0 =C2=A0*()
> =C2=A0 =C2=A0^
> SyntaxError: invalid syntax

It's worth reading the Python tutorial.  Here's the relevant section:

http://docs.python.org/tutorial/controlflow.html#unpacking-argument-lists

You could read all of 4.7

--=20
Arnaud