VIS (Vapourware Interface Synthesiser) questions

[Sascha Silbe]

Hi!

First of all, sorry for being offtopic. VIS[1] has been discussed here 
before and there's quite some overlap between the target audiences of 
VIS and ion. If there's anyone annoyed by this thread, please tell me 
and I'll continue this off-list.

I'm currently trying to write a prototype implementation for VIS, but 
some things were not quite clear (at least to me) in the paper:

1. Vis.Command is mentioned/used, but not defined anywhere. I've 
currently made it a child of Accessible with getv() and setv(v) 
returning/expecting a function. I presume it's not supposed to be 
user-visible, so I'm not sure that's the right approach.

2. Are the parameters to Vis.Command specified in the name (separated by 
dots) string literals or variable names?

3. How exactly are Sets expected to work? What's meant with "set (of 
sets) that is a cross-section of the sets in the hierarchy" (Section 
5.1, Vis.Struct:get)? Some examples would be great.

4. What is vis.Context:clear() expected to clear? Only the "internal" 
state or the defined Accessibles, too?

5. What's expected to happen if there are both 'std/foo' and 
'libbar/foo'? Raise a name collision exception?

6. In Section 5.2, fifth paragraph, it's defined that command entries 
must end in '()'. But several occurances of command definition examples 
(like "ctx:def('std/content.location:changed', vis.Command)" in the box 
at the end of section 5.3) don't use that notation. Is that a typo or 
have I overlooked something?

7. How is Context:realise() expected to work? When does it return? How 
does it interact with std/seq.next() and vis.mainloop()?

8. What are the parameters of foo:changed? Canvas containing foo and foo 
itself (example in section 6.2, function set_viewarea)? What if it's 
used below vis.maincontext() instead of below vis.create_canvas()?


[1] http://modeemi.cs.tut.fi/~tuomov/vis/vis-paper/

CU Sascha

--
http://sascha.silbe.org/



pgpjrTTG8mWU3.pgp
Description: PGP signature