6 Commits

Author	SHA1	Message	Date
Holly Borla	6e8a581b42	[LangOptions] Remove the option to enable/disable implicit existential ... opening.	2022-06-27 18:03:20 -07:00
Doug Gregor	0927c9f2fa	Restrict implicit opening of existentials based on the generic function's requirements ... Rather than looking solely at the existential argument of a generic function to determine whether it self-conforms, compare the existential argument against each of the protocols to which the corresponding generic parameter conforms. This better models when the existential value itself will successfully meet the requirements of the generic function, and therefore not require opening. This provides far better source compatibility by not changing semantics of existing, well-formed calls, and eliminates the need to special-case CoW-related operations in the standard library.	2022-03-29 11:59:29 -07:00
Doug Gregor	0ca06295bc	Suppress opened existentials for self-conforming existential metatype arguments	2022-03-28 18:48:17 -07:00
Doug Gregor	945790a6f5	as! and as? also indicate suppression of implicit existential opening	2022-03-28 13:33:29 -07:00
Doug Gregor	25e71a3a3b	Don't open an existential argument that's completely self-conforming. ... Such existential arguments will already meet the requirements of a generic function they are passed to, but would change runtime semantics. Therefore, don't open the existential in such cases.	2022-03-24 13:08:00 -07:00
Doug Gregor	02a13f3507	Allow explicit "as <existential-type>" to disable implicit opening of existentials	2022-03-08 10:31:35 -08:00