[ clisp-Feature Requests-3545986 ] Add ABORT restart to threads

[SourceForge.net <no...@so...>]

Feature Requests item #3545986, was opened at 2012-07-19 11:03
Message generated for change (Comment added) made by 
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=351355&aid=3545986&group_id=1355

Please note that this message will contain a full copy of the comment thread,
including the initial issue submission, for this request,
not just the latest update.
Category: UI
Group: None
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: lmj ()
Assigned to: Vladimir Tzankov (vtz)
Summary: Add ABORT restart to threads

Initial Comment:
* "Implementors are encouraged to make sure that there is always a restart named abort around any user code so that user code can call abort at any time ... in some batch or multi-processing situations there may be situations in which having it kill the running process is more appropriate." http://clhs.lisp.se/Body/r_abort.htm

* There's nothing to do inside the debugger with no restarts; the 'a' key in SLIME doesn't work.

* Since bordeaux-threads does not permit a thread to kill itself, there is no implementation-neutral way of self-terminating a thread outside of invoking ABORT (or establishing some other restart beforehand).

* User code which has already added an ABORT restart is OK, since the user's ABORT will hide the new topmost ABORT.

* Peer pressure: these implementations define ABORT inside threads: ABCL, Allegro, Clozure, ECL, LispWorks, SBCL.

----------------------------------------------------------------------

Comment By: lmj ()
Date: 2012-07-20 05:03

Message:
I'm not sure I understand your point. The standard draws a distinction
between a REPL process and other processes.

"Typically, in an interactive listener, the invocation of abort returns to
the Lisp reader phase of the Lisp read-eval-print loop, though in some
batch or multi-processing situations there may be situations in which
having it kill the running process is more appropriate."
http://clhs.lisp.se/Body/r_abort.htm

So the main REPL thread is already doing what the standard suggests.

----------------------------------------------------------------------

Comment By: Vladimir Tzankov (vtz)
Date: 2012-07-20 03:28

Message:
Currently we throw special tag in the context of the thread in order to
cause it to exit - I can replace this with abort restart.
However what to do with the "main" thread - should we do the same? It is
not good to treat it specially.

----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=351355&aid=3545986&group_id=1355