Subject: bug#48134: When sitting on top of a M-x item in the manual

From: Lars Ingebrigtsen <[email-masked]>
Date: Mon, 03 May 2021 11:00:44 +0200

Kévin Le Gouguec <[email-masked]> writes:

> I see that (info "(emacs) Minibuffer History") mentions its DWIM
> behaviour and gives examples for filename prompts, but given how
> ubiquitous and useful M-n is, I wonder if we couldn't do more to
> advertise it.

Yeah, it is perhaps a too-hidden feature.

> I realize that this would probably not be trivial to implement though.
> Looking up "future history in minibuffer input" in the Elisp manual
> brought me to (info "(elisp) Text from Minibuffer"), which lured me into
> thinking that this hypothetical hint could simply be added in
> read-from-minibuffer, by looking at the DEFAULT argument; a stroll
> through read-extended-command taught me that some functions compute
> their "future history" dynamically with minibuffer-default-add-function,
> which I guess complicates things a bit?

Yes, in general we don't really know whether we have anything in the
future history until the user hits `M-n', I think?  We could say
something in the instances where we do know in advance, but users might
infer from that that there's nothing in `M-n' if the message doesn't
appear.  And saying "M-n might reveal something" isn't very helpful
either.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no