bug#55853: 28.1; Please document f#(...) syntax in Elisp manual

[Lars Ingebrigtsen <larsi@gnus.org>]

Drew Adams <drew.adams@oracle.com> writes:

> See https://stackoverflow.com/q/72547221/729907.
>
> Users see this #f(...) syntax.  They should be able to consult the doc
> in some way to find out what it is/means.  Please consider documenting
> it in the Elisp manual.  Thx.

From the URL:

The syntax in question is in the following expression

((remote . emacs)
 (system . #f(compiled-function
          (file path)
          #<bytecode -0x47e8150df949387>))
 (t . #f(compiled-function
     (file path)
     #<bytecode -0x47e8150df949387>)))

It's from:

(cl-defmethod cl-print-object ((object compiled-function) stream)
  (unless stream (setq stream standard-output))
  ;; We use "#f(...)" rather than "#<...>" so that pp.el gives better results.
  (princ "#f(compiled-function " stream)

I.e., it's from the "pretty" version of prin1, and is not meant to be
readable by the Lisp reader.

I've now mentioned this in the Special Read Syntax node in the lispref
manual in Emacs 28.2.

-- 
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