Sema: Fudge backward compatibility for init special declname [4.2]
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…lling as special declname
In Swift 4, constructors had the same name as properties,
methods and enum cases named `init`. This meant that you
could use constructor syntax to call such a member, which
caused some confusing behavior.
Recently I added a special declname for `init` so that
constructors have unique names distinct from any name you
can spell, and "foo.init" syntax would look for a member
with the special name rather than one named `init`.
Unfortunately people actually had code where they defined
members named `init` and then use them via normal member
lookup syntax, like this:
enum E {
case `init`
}
let e: E = E.init
So to maintain backward compatibility, hack member lookup
to also find members named `init` when looking up the special
declname for constructors.
The workaround is only enabled in Swift 4 and 4.2 mode;
in Swift 5 mode you are expected to write "foo.`init`" to access
non-constructor members named `init`.
Fixes <rdar://problem/38682258>.
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In Swift 4, constructors had the same name as properties,
methods and enum cases named
init. This meant that youcould use constructor syntax to call such a member, which
caused some confusing behavior.
Recently I added a special declname for
initso thatconstructors have unique names distinct from any name you
can spell, and "foo.init" syntax would look for a member
with the special name rather than one named
init.Unfortunately people actually had code where they defined
members named
initand then use them via normal memberlookup syntax, like this:
So to maintain backward compatibility, hack member lookup
to also find members named
initwhen looking up the specialdeclname for constructors.
The workaround is only enabled in Swift 4 and 4.2 mode;
in Swift 5 mode you are expected to write "foo.
init" to accessnon-constructor members named
init.Fixes rdar://problem/38682258.