bug#61609: 26.3; Doc strings of `just-one-space` and `delete-horizontal-space'

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

Please mention in the doc strings that a prefix arg is how you get the
behavior described for the argument.  The doc strings don't seem to be
properly written for users.

  just-one-space:

  Delete all spaces and tabs around point, leaving one space (or N spaces).
  If N is negative, delete newlines as well, leaving -N spaces.

  delete-horizontal-space:

  Delete all spaces and tabs around point.
  If BACKWARD-ONLY is non-nil, only delete them before point.

Nothing tells you that N for `just-one-space' is the numeric prefix arg
or that BACKWARD-ONLY for `delete-horizontal-space' is the (raw) prefix
arg.  Without checking the code users won't have a clue how to get the N
and BACKWORD-ONLY behaviors.

(The descriptions in the manual do provide this info that's missing from
the doc strings.)


In GNU Emacs 26.3 (build 1, x86_64-w64-mingw32)
 of 2019-08-29
Repository revision: 96dd0196c28bc36779584e47fffcca433c9309cd
Windowing system distributor `Microsoft Corp.', version 10.0.19044
Configured using:
 `configure --without-dbus --host=x86_64-w64-mingw32
 --without-compress-install 'CFLAGS=-O2 -static -g3''