Support C-h S (info-lookup-symbol) in helpful-mode

[xuchunyang]

C-h S (info-lookup-symbol) is for searching Info manual base on the Major mode, for helpful-mode, since it's related to Emacs, C-h S should search Emacs-related info manuals, like help-mode.

Not sure about the correct way, but I found the following works for me.

(info-lookup-maybe-add-help
 :mode 'helpful-mode
 :regexp "[^][()`'‘’,:\" \t\n]+"
 :other-modes '(emacs-lisp-mode))

(info-lookup-maybe-add-help
 :mode 'elisp-refs-mode
 :regexp "[^][()`'‘’,:\" \t\n]+"
 :other-modes '(emacs-lisp-mode))

changed from (in the end of info-look.el)

(info-lookup-maybe-add-help
 :mode 'help-mode
 :regexp "[^][()`'‘’,:\" \t\n]+"
 :other-modes '(emacs-lisp-mode))

[Wilfred]

I think this is duplicate of #7. I'd like to have something like:

Documentation
If COND yields non-nil, do BODY, else return nil.

When COND yields non-nil, eval BODY forms sequentially and return
value of last one, or nil if there are none.

[View in manual]

We would then only show the button if the symbol was available in the manual.

Does this meet your need? I've never seen info-lookup-symbol before, so I may have misunderstood.

[Wilfred]

I believe this has been sorted by #7 and #32.