Wingman: Ensure homomorphic destruct covers all constructors in the domain#1968
Merged
mergify[bot] merged 6 commits intohaskell:masterfrom Jun 25, 2021
Merged
Conversation
pepeiborra
approved these changes
Jun 23, 2021
jneira
pushed a commit
to jneira/haskell-language-server
that referenced
this pull request
Jun 25, 2021
…omain (haskell#1968) * Ensure homomorphism covers the entire codomain * Add tests * Add the same logic to lambda case homomorphism Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
This PR changes the behavior of the
homotactic, ensuring that it is total and well-typed to apply. Before, it would just automatically fill in the data constructors, regardless of whether they were the right type. The new logic is to check which data constructors are possible in the domain, and which in the codomain, and to subtract the latter from the former. If this set is non-empty, it means either the thing won't type check, or that due to some GADT equalities, it's impossible to map some constructors. Either way, the tactic should fail, and does now.Fixes #565