bug#14238: [PATCH] Help page for character description forgets the character

[Kelly Dean <kellydeanch@yahoo.com>]

--- On Mon, 4/22/13, Stefan Monnier <monnier@iro.umontreal.ca> wrote:
> Not sure if it is really a bug: while the name is
> "describe-char" what
> it does is more like "describe-pos" (and indeed it receives
> a position
> rather than a char as argument).
> 
> So when you "back" you ask to redisplay the info about the
> pos where
> A used to be (and where C is now instead).
> 
> The data stored with `help-setup-xref' is also used for
> `revert-buffer'
> which lets you refresh the description after the buffer was
> modified.

Put point on a function name, and do C-h f RET, then again on another function name. Then delete the first function name and type a new one, and do back in the help buffer. The documentation for the original first function name is displayed, not for the new one. Surely Emacs's behavior in this case is correct. Why then is it correct for describe-char to follow changes in the source buffer, if describe-function doesn't? I don't see how it's a useful feature. All it does it cause problems: one, after browsing a series of help pages, you go back to review the character description you looked at, and it's gone; two, there's an unexpected character description in your history, and you're left futilely trying to remember why you looked up the description for that character.