If I need to use an array in an ofelia script, what is the best way?

Lua tutorials tell me that you need to start with an empty array or array literal, enclosed in curly braces. Fair enough.

If I type M.array = {} into an object box, the PD GUI chokes on it and says "keycode 123: dropped."

If I create [ofelia f blahblah], exit edit mode, click on the box to open the text window, put in some code, close the window, and save the patch, the code does not get saved.

I was able to get it to work by writing the script in an external file and [read ...(-ing it into an [ofelia d] object. (Now the .pd file is no longer self-contained.)

I'm OK with that for my own use, but within a few months, I will need to sell that to some students. "You can write a simple script directly into the object, but... oh no wait, if you use arrays, then you have to walk around the block first."

Or is there another Lua syntax for arrays? Just wondering how this is handled.

hjh

@ddw_music I still haven't had time to install and play with ofelia, but I think [ofelia define] is what you need......https://forum.pdpatchrepo.info/topic/11781/ofelia-lua-table-and-a-few-questions
The array can then be stored in the patch if that is required..
David.

@whale-av "but I think [ofelia define] is what you need"

Hm, OK, so I tried the same steps with an [ofelia d] object instead of [ofelia f]:

1. Create [ofelia d hjhtest]
2. Ctrl-E to drop out of edit mode.
3. Click on the [ofelia d...] to open its notepad.
4. Type M.flibble = "flobble"; (doesn't matter what it is).
5. Save the patch.
6. Open the patch file in Emacs, and see no evidence of the notepad contents:

   #N canvas 658 185 450 300 12;
   #X obj 135 76 ofelia d hjhtest;
   

7. Close and reopen the saved patch.
8. Click on the [ofelia d...] and find that the notepad is empty.

So the notepad contents seem to be in memory only.

hjh

@ddw_music -k switch..... to save within the patch?
It looks very much like the [text] object.
David.

@whale-av said:

It looks very much like the [text] object.

Yes, [ofelia define -k] is the way to «embed» a script in a Pd patch. You can send a [clear, read -c script.lua( message to load the script, like in a [text] object.

@ddw_music said:

Or is there another Lua syntax for arrays? Just wondering how this is handled.

Like you say the right way to define arrays in Lua is M.array={}, Pd will complain if you use that in an object, but will let you do it in the «script view» of an [ofelia -k define] object.

Another approach would be to use the Pd bindings, this way you define an array in Pd with a unique name (array-1) and you can read it directly in an [ofelia function] object.

Ah, OK, -k -- I had missed that.

Also interesting to be able to interface with pd arrays. That will be useful in some cases. The specific thing I was trying to do yesterday was to generate random positions for rectangles, and retain them so that they don't move on every ofDraw cycle. In that case it should be internal.

I'm thinking, though, that I might stick with external script files, because...

It dawned on me yesterday, when I got draw errors flooding the console for the umpteenth time, that instead of breaking and re-creating the connection between [ofDraw] and its descendents, I could stick a [spigot] in between and control it with a toggle. That led to the idea of a graph-on-parent abstraction (left inlet comes from [ofDraw] -> [ofRequire] -> etc., right inlet is a script path to read)... but AFAICS you can't programmatically open the contents of an [ofelia] box (no message you can send to it), so if I use this abstraction, then to edit the script, I would have to open the abstraction and then open the script... well, that's no fun.

It was also working quite well yesterday to edit the Lua code in Emacs and just click the [read...( box to update.

But thanks for -k -- I had simply overlooked its significance. And it means, if I load the script from disk, it gets saved as a default script for next time.

hjh