Ticket #1091 (closed deprecation: wontfix)

Opened 12 years ago

Last modified 11 years ago

ExceptionHandlers should be Subs

Reported by: whiteknight Owned by:
Priority: normal Milestone:
Component: core Version: 1.6.0
Severity: medium Keywords: exception
Cc: Language:
Patch status: Platform:


ExceptionHandlers are currently continuations that point to a label. When the handler is called, it jumps to that label and executes in the context of the sub where it was defined. This creates some problems, most notably the inferior runloop problem.

Continuation-based ExceptionHandlers are deprecated after 2.0.

Change History

Changed 12 years ago by pmichaud

I've just sent a message to parrot-dev outlining why I find this proposed deprecation problematic and asking for clairification -- see  http://lists.parrot.org/pipermail/parrot-dev/2009-December/003479.html .

Also, the original ticket description claims that inferior runloops are a side effect of the current label-based exception mechanism... but I don't believe that the use of labels have anything to do with that problem either. Some clarification (an example showing inferior runloop generation and how "ExceptionHandlers as Subs" avoids that problem) would be helpful to me here.

Until it's clearly defined how the proposed replacement will be able to handle control exceptions for HLL loops and subroutines, I'd like to see this deprecation notice postponed indefinitely.



Changed 12 years ago by chromatic

  • milestone changed from 2.0 to 2.1

Changed 12 years ago by coke

  • type changed from todo to deprecated
  • milestone 2.1 deleted

Changed 12 years ago by jkeenan

Are we going to pursue this ticket at any time in, say, the next three months?

If not, I think we should reject it.

Thank you very much.


Changed 11 years ago by whiteknight

  • status changed from new to closed
  • resolution set to wontfix

I think that we are not going to pursue this. The finalize opcode (which was recently taken off the experimental list) is the canonical solution to the inferior runloops problem, so there is no longer a pressing need for sub-based exception handlers. I'm going to close this ticket.

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