Okay, I got this to work in org-babel in a file foo.org
that has headlines like this:

* Foo.org     :bar:

#+BEGIN_SRC emacs-lisp

(org-scan-tags 'agenda ;; Action
                      '(lambda (todo tags-list level)  ;; Matcher
                               (progn
                                    (setq org-cached-props nil)
                                    (member "bar" tags-list))) ;; End
Matcher
                       org--matcher-tags-todo-only) ;; Todo-only
#+END_SRC

I removed the "staff" from the beginning of the function call, and changed
staff to "bar"  I also removed the (or (and)) conditions :-)

Now, I need to see how to make this function search all agenda files - it
seems
to work only on the headlines in Foo.org

Thanks,
--Nate

On Thu, Aug 8, 2019 at 3:03 PM Nathan Neff <nathan.neff@gmail.com> wrote:

> Hi Jean,
>
> Thank you - however, I can't get this function to return anything.
>
> org-scan-tags accepts an action, a matcher and a todo-only.
>
> Code:
>
> (org-scan-tags 'agenda ;; Action
>                       '(staff lambda (todo tags-list level)  ;; Matcher
>                                (progn
>                                     (setq org-cached-props nil)
>                                     (or (and (member staff tags-list)))))
> ;; End Matcher
>                        org--matcher-tags-todo-only) ;; Todo-only
>
> * To my knowledge, the 'agenda is the action, and the list starting with
> `(staff <snip>) is the matcher.
> * Why does the tag I'm searching for ("staff") appear as the first "atom"
> in the
> "matcher" parameter?  Why isn't it just a lambda?
> * I don't quite understand what the "or" and "and" are doing.  It seems
> like
> I don't need either of them.
>
> My org-agenda-files contains files and I have a headline with the tag
> "staff"
> - no quotes, and the function's not returning anything.
>
> Thanks,
> --Nate
>
>
> On Thu, Aug 8, 2019 at 2:13 PM Jean Louis <bugs@gnu.support> wrote:
>
>> * Nathan Neff <nathan.neff@gmail.com> [2019-08-08 18:50]:
>> > Hello all,
>> >
>> > Has anyone created a Helm source from the results of org-agenda?
>> >
>> > Specifically org-tags-view I think would be a cool Helm source to
>> > configure where the headings that have certain tags could be displayed
>> > by Helm.
>> >
>> > I looked @ the code for org-tags-view and it's fairly straight
>> > forward - however, I think that the function itself is tightly
>> > coupled between finding the results and displaying the results.  In
>> > other words, there's no easy function that I see which would provide
>> > headings that match a tags search that I could use as a Helm source.
>>
>> If tag is 'staff, this below will give structure out:
>>
>> (org-scan-tags 'agenda '(staff lambda (todo tags-list level) (progn
>> (setq org-cached-props nil) (or (and (member staff tags-list)))))
>> org--matcher-tags-todo-only)
>>
>> Now `org-scan-tags` could be inspected if it constructs some lists,
>> alist, that are somewhat nicer than such output.
>>
>> But that output can be converted to HELM completion.
>>
>> Jean
>>
>