bug#22692: 25.0.91; xref-find-definitions fails to prompt

[Mike Kupfer <m.kupfer@acm.org>]

Dmitry Gutov wrote:

> On 02/16/2016 03:02 AM, Mike Kupfer wrote:
> > If point is on a token that isn't defined in the current tags file,
> > M-. gives me an error (look for "Cygwin" further down in this bug
> > report).  I expect to get a prompt.
> 
> That doesn't sound right to me: "XXX is not found" is a valid piece of
> information. Simply showing a prompt would obscure it.

The Help string for xref-find-definitions says

> With prefix argument or when there’s no identifier at point,
> prompt for it.

I guess you could argue that if point is on a token that's not in the
tags table, it's still on an "identifier".  But "#" is hardly an
identifier.

And the Info page "Xref Commands" says

> With a prefix argument, or if there’s no valid
> identifier at point, it prompts for the identifier.

Does "valid identifier" mean syntatically correct, or does it mean that
the identifier is in the tags table.  Please clarify the documentation.

> If we accept that the command searches for the thing at point by
> default, the current behavior seems appropriate. And whether or not it
> prompts, is customizable.

Yes, I have already have

  (setq xref-prompt-for-identifier t)

in my .emacs.

mike