RE: option doc strings and Customize tags

["Drew Adams" <drew.adams@oracle.com>]

> I think we should just add the value to the menu, together with some
> sanity check: if the printed representation of the value is too long,
> then shorten it by replacing the middle chars with "...", and let the
> code provide an override for those few remaining cases where it's
> not satisfactory.

That's the abbreviating I suggested. But I'd recommend eliding the terminal
chars, not the middle ones. In the case of a sexp, the normal elision should be
used (e.g. via `print-length') - such as is used in *Backtrace*, but more
abbreviated.

But don't you agree that we need really to provide the value only when it is a
symbol-valued `const' in a `choice'? I think those are about the only cases
where a doc string's reference to a value might lead to confusion wrt the
Customize tags.

If so, then there is no need to worry about sexps and strings and such. It is
only the occasional long symbol name that would need to be abbreviated (at its
end, not middle).