Re: Printing an alist of plists with cons format

On Mon, Mar 23, 2026 at 7:47 PM Heime <[email protected]> wrote:

> ((:cm :10pt 283.46456 :pt 28.34646 :mm 10 :in 0.3937 :ft 0.03281)
>  (:in :10pt 720 :pt 72 :mm 25.4 :cm 2.54 :ft 0.083333)
>  (:ft :10pt 8640 :pt 864 :mm 304.8 :cm 30.48 :in 12))
>
> How can I get the new list being printed as
>
> ((:cm . (:10pt 283.46456 :pt 28.34646 :mm 10 :in 0.3937 :ft 0.03281))
>  (:in . (:10pt 720 :pt 72 :mm 25.4 :cm 2.54 :ft 0.083333))
>  (:ft . (:10pt 8640 :pt 864 :mm 304.8 :cm 30.48 :in 12)))

Nohow, barring a custom prettyprinter. These are two equivalent forms,
and there is no information in the data structure that encodes which
form you’d prefer.

    (equal
     '((:cm . (:10pt 283.46456 :pt 28.34646 :mm 10 :in 0.3937 :ft 0.03281))
       (:in . (:10pt 720 :pt 72 :mm 25.4 :cm 2.54 :ft 0.083333))
       (:ft . (:10pt 8640 :pt 864 :mm 304.8 :cm 30.48 :in 12)))
     '((:cm :10pt 283.46456 :pt 28.34646 :mm 10 :in 0.3937 :ft 0.03281)
       (:in :10pt 720 :pt 72 :mm 25.4 :cm 2.54 :ft 0.083333)
       (:ft :10pt 8640 :pt 864 :mm 304.8 :cm 30.48 :in 12)))
    ⇒ t

    (defun pp-aplist (aplist)
      (format "(%s)"
              (mapconcat (lambda (pair)
                           (format "(%s . %s)" (car pair) (cdr pair)))
                         aplist "\n ")))

    (pp-aplist '((:cm :10pt 283.46456 :pt 28.34646 :mm 10 :in 0.3937
:ft 0.03281)
                 (:in :10pt 720 :pt 72 :mm 25.4 :cm 2.54 :ft 0.083333)
                 (:ft :10pt 8640 :pt 864 :mm 304.8 :cm 30.48 :in 12)))
    ⇒ "((:cm . (:10pt 283.46456 :pt 28.34646 :mm 10 :in 0.3937 :ft 0.03281))
        (:in . (:10pt 720 :pt 72 :mm 25.4 :cm 2.54 :ft 0.083333))
        (:ft . (:10pt 8640 :pt 864 :mm 304.8 :cm 30.48 :in 12)))"