Re: [O] Testers / Feedback wanted: Gantt charts via org-gantt.el

[Bernhard Schmitz]

Hi Karl, hi Eric,

I know it has been a while. I think every suggestion has been implemented by 
now, except for linking independent headlines.
I wanted to ask for your input again, as I'm still not sure how to handle this, 
and both of your suggestions seemed to fall into the same category for me.

* Eric S Fraga <address@hidden> wrote:
>
> The only comments I have at the moment is that it is missing support for
> milestones and all of my GANTT charts have such and that I would like to
> be able to link tasks across headlines (i.e. groups).  Can I suggest a
>:milestone: tag or MILESTONE property for the former and a LINKED-TO or
> similar for the latter?

Should this link only be a graphical link, or should the start time of the 
second headline be determined by the end time of the first (as it is done with 
ordered headlines)? Or can what you have in mind be expressed by org-depend 
(see below)?

Karl:

> Oh, I was too lazy to write a working example.
> 
> ,----[ working example ]
> | ** DONE My pretty task
> | CLOSED: [2015-04-30 Thu 07:50] SCHEDULED: <2015-04-30 Thu>
> | :PROPERTIES:
> | :CREATED:  [2015-04-17 Fri 15:36]
> | :ID:       2015-04-17-Dach-zu
> | :TRIGGER:  foo1(NEXT) bar1(WAITING)
> | :BLOCKER:  previousXY prevZ
> | :END:
> `----
> 
> So when this task got marked as DONE, the headings with the ID
> propertes "previousXY" and "prevZ" must not have been in an open
> state. Further more, the headings with ID "foo1" got the new states
> NEXT and "bar1" WAITING accordingly.

Your example clarified the effects of org-depend on the actual org file, but 
I'm not sure how this should translate to the gantt chart.
The :BLOCKER: property says that when this gets marked as done, the blockers 
must not be open. So actually, the :BLOCKER: property has no effect on either 
the start time, nor on the end time of a headline. It only clarifies the 
earliest possible end time - which cannot be expressed in a gantt chart.
Similarly, the :TRIGGER: property does not define a start or an end time of the 
triggered property either. The only case in which it does is if it triggers a 
(DONE), which would mean that an unrelated task suddenly becomes done simply by 
another task being done, and I don't think that happens all too often.

I now know that I can implement whatever you suggest with relatively little 
effort, but first I need to know what actually should happen.

Regards,
Bernhard