I recommend looking into org-edna
(http://www.nongnu.org/org-edna-el/#conditional_forms).
You can try to use "has-property" in combination with "set-property" as
a TRIGGER.

Alternatively, you can customize org-property-changed-functions (see
https://www.reddit.com/r/emacs/comments/7gr9ps/add_logbook_entry_and_note_on_orgmode_property/)
and reimplement org-edna functionality for your purposes.

Regards,
Ihor

cpb <cpb@snotbubble.com> writes:

> Is there a way to set properties using other properties?  Doesn't matter
> if its on export only, though it would be nice to have it in-situ.
>
> here's an example (obviously doesn't work), where a project properties
> for the project client only needs the CLIENT property filled, the rest
> of it automatically populates on export.  Would save having to duplicate
> the data where there are a lot of projects.
>
>
> * client1
>     :PROPERTIES:
>     :CUSTOM_ID:        client1
>     :NAME:             a client
>     :ADDRESS:          an address
>     :EMAIL:            an email
>     :URL:              a website
>     :END:
>
> * project1
>     :PROPERTIES:
>     :CUSTOM_ID:        project1
>     :NAME:             a project
>     :CLIENT:           client1
>     :CLIENT_NAME:      {{{property(NAME,#{{{property(CLIENT)}}})}}}
>     :CLIENT_ADDRESS:   {{{property(ADDRESS,#{{{property(CLIENT)}}})}}}
>     :CLIENT_EMAIL:     {{{property(EMAIL,#{{{property(CLIENT)}}})}}}
>     :EXPORT_FILE_NAME: ./a_project
>     :END:
>
>     project....: {{{property(NAME)}}}
>     for........: {{{property(CLIENT)}}}
>                  {{{property(CLIENT_ADDRESS)}}}
>                  {{{property(CLIENT_EMAIL)}}}
>

-- 
Ihor Radchenko,
PhD Student
Singapore University of Technology and Design,
8 Somapah Road Singapore 487372
Email: yantar92@gmail.com, ihor_radchenko@mymail.sutd.edu.sg
Tel: +6584017977