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[Python-Dev] Order of positional and keyword arguments

Antoine Pitrou solipsis at pitrou.net
Fri Apr 27 05:59:38 EDT 2018 
On Thu, 26 Apr 2018 22:25:09 +0300
Serhiy Storchaka <storchaka at gmail.com> wrote:
> 
> f(b=2, *[1]) is surprised in two ways:
> 
> 1. Argument values are passed not in order. The first value is assigned 
> to the second parameter, and the second value is assigned to the first 
> parameter.

I don't find it that surprising.  If you write f(b=2, a=1), you are
also passing arguments "not in order", but it still looks ok to me.

> 2. Argument values are evaluated not from left to right. This 
> contradicts the general rule that expressions are evaluated from left to 
> right (with few known exceptions).

Well... If you have code that relies on that rule, I would agree it's
brittle code and should be rewritten differently (perhaps by assigning
to temporary variables explicitly).

Regards

Antoine.
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