sempass2: lift capture restriction #1427
Merged
Conversation
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
Given the nested procedures `a: b: c:`, where `c` closes over a local of `a`, `c` effectively captures from `b` and `b` captures from `a`. A procedure usable in both a compile- and run-time context may capture from a compile-time-only procedure, so the aforementioned should work when `a` is a compile-time-only procedure and the others are not, but it was forbidden in practice. The restriction is now lifted, and the code implementing the test restructured to be more intelligible.
zerbina
added
compiler/sem
saem
approved these changes
Aug 21, 2024
|
/merge |
|
Merge requested by: @saem Contents after the first section break of the PR description has been removed and preserved below:
|
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Outdated suggestions cannot be applied.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.
Summary
Procedures useable in both compile- and run-time contexts can now close
over compile-time-only locals even if nested in another procedure
usable in both contexts.
Fixes #1425.
Details
Given the nested procedures
a: b: c:, whereccloses over a localof
a,ceffectively captures frombandbcaptures froma.A procedure usable in both a compile- and run-time context may capture
from a compile-time-only procedure, so the aforementioned should work
when
ais a compile-time-only procedure and the others are not, sinceccan legally borrow frombandbfroma, but it was disallowedin practice.
The arbitrary restriction is now lifted, and the code implementing the
test restructured to be easier to understand.