Disable distribution of intersection types over applied types #23441
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EugeneFlesselle force-pushed the distributeAnd branch 4 times, most recently from 2daa02b to 6171b84 Compare EugeneFlesselle added a commit to dotty-staging/dotty that referenced this pull request Jul 17, 2025
EugeneFlesselle added a commit to dotty-staging/dotty that referenced this pull request Jul 18, 2025
EugeneFlesselle force-pushed the distributeAnd branch from 7bf9c7d to 6b20da7 Compare And add minimization
Instead of AppliedType of OrTypes, which relied on the distribution of AndTypes when inheriting multiple context bound companions of the same name
EugeneFlesselle force-pushed the distributeAnd branch from 6b20da7 to 73214ff Compare 
odersky requested changes Sep 10, 2025
This reverts commit 0441af0 to resolve merge conflict
odersky approved these changes Sep 13, 2025
hamzaremmal added a commit to scala/scala-parallel-collections that referenced this pull request Sep 18, 2025
Starting from Scala 3.8.0, the following code will not compile due to removing some unsound typing rules. See scala/scala3#23441 Co-authored-by: Eugene Flesselle <eugene@flesselle.net>
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Fixes soundness issue #23435
Note in particular that this implies we cannot (indirectly) inherit multiple instantiations of the same trait. E.g., see tests/neg/conflicting-inst-basetypes.scala.
The impact on the community-build appears to be rather reasonable, tweaks are required:
The changes should be relatively well regrouped by commit for review.