On Thu, Apr 14, 2022 at 3:28 PM I wrote:
> Conceptually, the debug thread mechanism could be hijacked as a
> synchronization mechanism.
At least in j904 beta b, this approach has a severe practical problem.
Here's an illustration of the underlying mechanics:
NB. ensure we have some threads
0&T.@'' each i.0>.4-1 T.''
NB. use a couple threads
{{6!:3 y if.1 do.echo y end.}} t.''"0] 10 11
NB. sync
13!:0]1
13!:15'joinImplementation 0'
joinImplementation=: {{
NB. synchronization mechanism would go here
echo '-------------'
echo '1 ',":1 T.''
echo '2 ',":2 T.''
echo '3 ',":3 T.''
echo 13!:1''
echo '-------------'
13!:5''
}}
test=: {{
echo 'a'
assert. 0
echo 'b'
}}
test''
When I run this script, I expected my debug latent expression to run
immediately. Instead, it does not run until all tasks have completed
their work. This behavior was not intended, if I understood correctly.
Additionally, the 13!:5'' does not resume execution -- I can work
around this by replacing that line with 9!:27'13!:5'''''[9!:29]1 so
that's less of an issue for now.
That said, my vision here was to define a 'sync' adverb which takes a
y argument, stores it in a task specific variable, and then uses
assert. to enter the debug sentence. The debug sentence would
recognize that 'sync' was used and would pick up the thread's y value
and execute u against it. I have not figured out how to read the debug
thread number, however, so I would have to inject that information
into the stack trace, and pull it out of the 13!:13'' result.
But... as you can see... this would be rather slow in beta b.
FYI,
--
Raul
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