Crazy script-only stack question

[Mark Waddingham]

On 2018-01-23 17:21, Geoff Canyon via use-livecode wrote:
> ​This actually raises another point (and I'm sure this is a discussion 
> that
> happened without me several years ago, but as long as we're here) is 
> there
> a reason to use "this me" which seems terribly awkward, over "the 
> behavior
> of me" which is to my ear far more straightforward​ (it didn't require 
> any
> additional code or syntax) if a bit more verbose?

There's a longish thread on the engine forum about this...

The 'behavior of me' works fine as long as you aren't using a chained 
behavior - in the latter case, it would only give you the behavior 
object directly attached to 'me' (i.e. the object the behavior's are 
acting on).

The need to actually get the object a behavior's script resides in is 
really quite a rare operation (the only reason I think it is useful at 
all in the context of script-only stacks being used for behaviors is for 
resolving paths to resources relative to the behavior script file) so in 
the end I plumped for something simple to add which wasn't going to 
cause any difficulties in implementation or potential ambiguities - its 
strangeness helps reinforce the fact 'are you sure you need to do this' 
as well :)

In actual fact, I wonder whether it is really needed at all for 
behaviors expressed as script only stacks - you can use 'the filename of 
stack <name of behavior>' - which is more verbose but means you can 
avoid 'this me'. (Given that if you change the name of a behavior, any 
references to it break, you are forced to choose your behavior names 
wisely - hence why we use reverse-dns notation in the IDE).

Pondering slightly, if we codify the notion of a script object (i.e. 
something which is just a script), then perhaps we could have:

   - this object (me): the object currently executing

   - this script (this me): the script currently executing

Perhaps something to consider in the future (I've not spent any time 
considering whether 'this script' might have a more useful 
connotation!).

>> I'd propose the following:
>> 
>>   script <script-name> with behavior <behavior-name>
>> 
>> Where <behavior-name> is resolved as a stack reference.
>> 
> 
> ​Sure, that sounds perfect​.

I did a patch for this whilst having coffee this morning:

    https://github.com/livecode/livecode/pull/6290

It garnered some discussion internally - mainly whether the idea of a 
'loadStack' message would be better. I think it was decided that 
'loadStack' (i.e. a message sent after a stack is loaded, but before 
opened - something which happens whenever you reference a stack via a 
chunk without a go/open verb) was an orthogonal thing (and a fair bit 
more difficult to implement!).

Still needs some tests and generally checking around the idea - but as 
it stands at the moment it seems like a reasonable addition.

Warmest Regards,

Mark.

-- 
Mark Waddingham ~ mark at livecode.com ~ http://www.livecode.com/
LiveCode: Everyone can create apps