Am I right in thinking that there are no API methods or properties (action code or osascript) which let us read or write the fold state of particular notes in outline view ?
Correct. What is the need for doing so?
Just fine-tuning for habitual cycles of reveal and hide.
(In TaskPaper and OmniOutliner for example, which have API for fold-state, I can set up the OrgMode patterns of visibility cycling)
But no matter – not a feature request (just checking) – and for some reason I prefer to do the outlining component of things in a fairly widget-free (non-modal) plain text context anyway (TaskPaper especially). Feels somehow faster and less encumbering.
(And easy enough to import TaskPaper ⇄ Tinderbox)
Tinderbox does appear to save this, though I’m not sure where†, and it is not a state exposed to action code.
† Outlines and Charts remember container expansion states from session to session. I’d make a note with just enough notes to reflect two sibling containers, one expanded, the other note and then look at the doc’s XML source. If you can find where the state is stored, you could use noe of your command line methods to query the XML for the expansion state.
A side note re OPML. OPML import to Tinderbox does not reflect the
<expansionState> data in the OPML source. In OPML export from Tinderbox the process involves OPML tagged ‘HTML’ export and it does not reflect container state as this is not accessible to the user.
The expansion state of a container or agent is a property of the tab — the view specification for the outline or chart.