The proposal was received favorably. The only major area of discussion was regarding the behavior of ~= and whether it should perform a full or partial match. Since a clear decision was not reached, the authors proposed, and the language work group agreed, to remove the operator from the proposal for now, allowing for more discussion post-Swift 5.7. Additionally, they would like to investigate the possibility of using named captures to effect bindings in case statements in the future, which may affect the implementation.
Thank you to everyone who participated in both the review.
There has been no further discussion of ~= for Regex at this point. It would begin with a pitch in the evolution section; such a pitch should focus primarily on laying out a clear rationale for why it is proposing either partial or whole match semantics for this operation (or something else), with a set of examples to argue that the proposed semantics are better than alternatives.