Re: how to speed up Lisp devel time

[Eli Zaretskii <eliz@gnu.org>]

> From: Emanuel Berg <incal@dataswamp.org>
> Date: Fri, 09 Aug 2024 09:16:52 +0200
> 
> One thing one could try is to replace boring, trivial stuff
> with non-Lisp syntax and have that embedded.
> 
> For example setting up the interface.
> 
> Note: Over one in five interfaces in the Emacs source uses
> Lisp and not the `interactive' format string. So it isn't just
> me. It takes _a lot_ of time setting up the interface,
> assigning default values, verifying indata, setting up
> collections for completion, and so on.
> 
> Here is one example from my own code:
> 
>   ;; ...
>   (interactive (if (numberp current-prefix-arg)
>                    (list current-prefix-arg)
>                  current-prefix-arg))
>   (unless end
>     (setq end 73))
>   (unless step
>     (setq step (min 10 (max 2 (/ end 10)))))
>   (unless i
>     (setq i 0))
>   (unless (and (numberp i)    (<= 0 i)
>                (numberp end)  (<  0 end)
>                (numberp step) (<  0 step))
>     (error "Bogus indata"))
> 
> This is 402 chars!

Why do you need that?  Interactive functions can supply the arguments
inside the 'interactive' spec, where no tests are needed.  And
non-interactive functions need not provide defaults for each argument,
at least not usually.

And finally, Emacs does have keyword arguments and cl-defun, if and
when you need these facilities.

Just look at the Emacs sources: you will rarely if ever find such long
sequences of setting missing arguments to their defaults.  That's no
accident.