On 2023-08-06  11:19, Jens Schmidt wrote:

> I
> will also add tests for matching property names having minuses and then
> we can see how it goes.

Went well.  With a property name regexp

   "\\(?5:[[:alnum:]_-]+\\)"

and the following Org file

--------------------------------------------------
* H1 :BAR:
:PROPERTIES:
:TEST-FOO: 1
:END:
* H2 :FOO:
:PROPERTIES:
:TEST-FOO: 2
:END:
* H3 :BAR:
:PROPERTIES:
:-FOO: 1
:END:
* H4 :FOO:
:PROPERTIES:
:-FOO: 2
:END:
* H5
--------------------------------------------------

the search expressions "TEST-FOO!=*0-FOO" and "-FOO+TEST-FOO!=*0" work
as expected, finding only the first heading.

The expression "-FOO!=*0-FOO" does *not* work, though, since the leading
minus in the property name is gobbled by the greedy inclusion/exclusion
subexp "\\(?1:[-+:]\\)?".  However, the remedy is simple: Add an
explicit plus sign: "+-FOO!=*0-FOO".

Documented that in the Org manual, added tests, looks good.  Please
check.