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Default value of keyword arguments John Cowan (03 Nov 2019 02:38 UTC)
Re: Default value of keyword arguments Lassi Kortela (03 Nov 2019 10:25 UTC)
Re: Default value of keyword arguments John Cowan (03 Nov 2019 21:24 UTC)
Re: Default value of keyword arguments Lassi Kortela (03 Nov 2019 21:44 UTC)
Re: Default value of keyword arguments Lassi Kortela (03 Nov 2019 21:52 UTC)
Re: Default value of keyword arguments John Cowan (03 Nov 2019 22:30 UTC)
Re: Default value of keyword arguments Lassi Kortela (03 Nov 2019 22:40 UTC)
Re: Default value of keyword arguments John Cowan (03 Nov 2019 23:27 UTC)
Re: Default value of keyword arguments Marc Nieper-Wißkirchen (03 Mar 2020 10:06 UTC)
Re: Default value of keyword arguments Lassi Kortela (03 Mar 2020 11:03 UTC)
Re: Default value of keyword arguments Lassi Kortela (03 Mar 2020 11:33 UTC)
Re: Default value of keyword arguments Marc Nieper-Wißkirchen (03 Mar 2020 12:50 UTC)
Re: Default value of keyword arguments Lassi Kortela (03 Mar 2020 13:19 UTC)
Re: Default value of keyword arguments Marc Feeley (03 Mar 2020 13:39 UTC)
Re: Default value of keyword arguments Lassi Kortela (03 Mar 2020 13:53 UTC)
Re: Default value of keyword arguments Marc Nieper-Wißkirchen (03 Mar 2020 14:33 UTC)
Re: Default value of keyword arguments Lassi Kortela (03 Mar 2020 15:00 UTC)
Re: Default value of keyword arguments Marc Nieper-Wißkirchen (03 Mar 2020 15:11 UTC)
Re: Default value of keyword arguments Lassi Kortela (03 Mar 2020 15:27 UTC)
Re: Default value of keyword arguments Marc Nieper-Wißkirchen (03 Mar 2020 15:51 UTC)
Re: Default value of keyword arguments Lassi Kortela (03 Mar 2020 16:06 UTC)
Re: Default value of keyword arguments John Cowan (03 Mar 2020 23:09 UTC)
Re: Default value of keyword arguments John Cowan (04 Mar 2020 17:09 UTC)
Re: Default value of keyword arguments Lassi Kortela (04 Mar 2020 17:20 UTC)
Re: Default value of keyword arguments Lassi Kortela (04 Mar 2020 17:33 UTC)
Re: Default value of keyword arguments Marc Nieper-Wißkirchen (04 Mar 2020 17:59 UTC)

Re: Default value of keyword arguments Lassi Kortela 04 Mar 2020 17:33 UTC

> - an implicit closure is created and the expressions generating default
> argument values are evaluated in that closure, remembering the old
> values (as in Python above).

Sorry, the Python example evaluates the default value expression once
only. It's also possible to evaluate the expression afresh every time a
default value is needed, but if it refers to variables inside some
closure, the semantics are confusing.

(defun proc1 (&key (foo foo)) ...)  <-- what happens?

(defun proc2 (&key (foo 1) (bar (+ foo 1))) ...)  <-- what happens?

These questions have answers in CL, but those answers are not obvious.