Re: prin1 / princ vs message ?

[Tino Calancha]

On Sun, 2 Jul 2017, Jean-Christophe Helary wrote:

> * Documentation about prin? family:
> (info "(elisp) Output Functions")
>
> * "The recommended way to show a message in the echo area is with the
>  `message' function, not `princ’".
>  Extracted from:
> (info "(elisp) Programming Tips")
>
> * `message' and the echo area:
> (info "(elisp) The Echo Area")
>
>
> Tino,
>
> I think that was pretty clear that I had actually read the documentation about 
> prin1, princ and message. So let me reiterate:
Appologies,  i misunderstood that.
> I am asking that because I am seeing code where standard-output is not set to 
> anything but it's default (the echo area) and still
> prin1/princ are preferred over message. So, why would a developer chose 
> prin1/princ over message when there is no stream argument
> (hence, when the output goes to standard output).
>
> The documentation seems to imply that message should be preferred, but are 
> there cases where prin1/princ are the best choice ?
In my case i use `message' most of the time.
I just use `prin?' things when i want to insert the printable 
representation of a lisp object withing a buffer.  Not so often, though.

In files, like
international/quail.el
or
international/mule-diag.el

note that they use the macro `with-output-to-temp-buffer', so they
must use `prin?' instead of `message' to collect the standard-output.

Even when `with-output-to-temp-buffer' is not called explicitely in
the file, like in
lisp/cus-theme.el

you better use `prin?' there, because those are messages related with
the Emacs help, i mean, they will appear in *Help* buffers which
are build binding standard-output.

Other than that i would stick with `message'.