This syntax is reserved to be likely used in the future as a shorthand for
"this::foo" where the resulting expression doesn't take the receiver as a
parameter but has "this" already bound to it
Resolve callable references taking into account expected callable types.
This affects call resolution procedure (resolve 'foo' in for 'foo(::bar)') similar to the approach used for function literals:
* During "shape arguments" phase of call resolution, callable references are resolved in independent context without expected type. If the callable reference is ambiguous, its shape type is a function placeholder type without parameter types and return type information. Otherwise, it is a reflection type for the resolved function or property. Upper-level call is resolved without taking into account ambiguous callable references.
* During "complete call" phase of call resolution, resolve callable reference arguments to actual descriptors (if possible), and update constraint system for the given call accordingly.
#KT-6982 Fixed
#KT-5780 Fixed
Without this, the unrelated type specified on the LHS of a property reference
literal was considered to be an extension receiver of the candidate, and the
resolution was erroneously successul. This is only reproducible for properties,
because if we're trying to resolve an extension, we consider all properties
from the scope, even non-extensions, because there may be a property of an
extension-functional type (T.() -> R). (We don't do this for functions.)
#KT-7430 Fixed
#KT-7945 Fixed
Alexander Udalov