POC: plugging the cancelable leak - #3491
Closed
armanbilge wants to merge 13 commits into
Closed
Conversation
reardonj
added a commit
to reardonj/cats-effect
that referenced
this pull request
Jul 18, 2026
In IO, cancelable can be implemented without hoisting the operation to a separate thread, by invoking the callback when cancelation is requested. Partly based on Arman's previous attempt in typelevel#3491 Co-authored-by: Arman Bilge <armanbilge@gmail.com>
reardonj
added a commit
to reardonj/cats-effect
that referenced
this pull request
Jul 18, 2026
In IO, cancelable can be implemented without hoisting the operation to a separate thread, by invoking the callback when cancelation is requested. Partly based on Arman's previous attempt in typelevel#3491 Co-authored-by: Arman Bilge <armanbilge@gmail.com>
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Implements a proof-of-concept for my proposal in #3474 (comment).
To re-iterate:
IO.Cancelable[+A](ioa: IO[A], cancel: IO[Unit])is now a primitive operationCancelable, it exposes itscanceloperation as part of thefiber.cancel.uncancelablesemantics, this guarantees that the final result ofioa(be it success, error, or cancellation) will always be propagated.As such, it plugs the leak.