Subject: bug#75170: add-to-alist: new function

From: "Alfred M. Szmidt" <[email-masked]>
Date: Tue, 21 Jan 2025 05:33:48 -0500

"Alfred M. Szmidt" <[email-masked]> writes:

   >    map-put! does not work well with alists that are not 'proper':
   >
   >        ELISP> (setq x (list 1 '(2 . 3)))
   >        (1 (2 . 3))
   >
   > Why should it work on alists at all?  map-put! assumes a map (where is
   > this structure documented? I did not see anything in the Elisp
   > manual), not an alist.  Invalid alists will also not work on functions
   > that assume alists.

   According to M-x describe-package RET map RET:

   map.el provides generic map-manipulation functions that work on
   alists, plists, hash-tables, and arrays.  All functions are
   prefixed with "map-".

That seems like it cannot possibly work (or very complicated).  How do
you differetnate between a plist and alist?  Order in an alist is
important, but not in a plist.  Their syntax is exactly the same, how
can a insertion function work correctly for that?

The above sounds like it is also overloading the concept of
sequencess?