Mathlib v3 is deprecated. Go to Mathlib v4

Commit 2021-06-13 11:45 6d2a0512

View on Github →

feat(algebra/covariant_and_contravariant): API for covariant_and_contravariant (#7889) This PR introduces more API for covariant and contravariant stuff . Besides the API, I have not actually made further use of the typeclasses or of the API. This happens in subsequent PRs. This is a step towards PR #7645.

Estimated changes