bug#19033: 25.0.50; (elisp) `Advising Named Functions' does not describe FUNCTION

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

This node sends you off to node `Core Advising Primitives' for
information about parameters WHERE and PROPS.

That's bad enough, since `Advising Named Functions' is intended as the
MAIN entry point for advising functions:

  "But you should use `advice-add' and `advice-remove' for that instead."

But `Advising Named Functions' tells you nothing about FUNCTION.  In
particular, it does not tell you what its signature must be or must fit.

Worse still, neither does node `Core Advising Primitives' tell you
anything about the signature of FUNCTION!  So it would not even be
enough to send readers to that node for information about FUNCTION,
as we do now for WHERE and PROPS.

What must FUNCTION accept as argument(s)?  What must it return?
If there are no restrictions on its signature, then say so.


In GNU Emacs 25.0.50.1 (i686-pc-mingw32)
 of 2014-10-20 on LEG570
Bzr revision: 118168 rgm@gnu.org-20141020195941-icp42t8ttcnud09g
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure --enable-checking=yes,glyphs CPPFLAGS=-DGLYPH_DEBUG=1'