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trait Equalizer[T]
trait Gen[A]
class Broken {
implicit def const[T](x: T): Gen[T] = ???
implicit def convertToEqualizer[T](left: T): Equalizer[T] = ???
def in(a: Any) = ()
in {
import scala.None // any import will do..
"" == "" // no longer a problem, see pos/t8129.scala
}
// We used to fall into the errant code path above when `Any#==` and `AnyRef#==`
// were overloaded.
//
// Real classes couldn't get away with that overloading; it would result in
// a compiler error because the variants would collapse into an overriding
// relationship after erasure.
//
//
// But, a structural type can! This triggers the same error, and served as
// a backstop for this test if we change the signatures of `AnyRef#==` to
// override `Any#==`.
type T = {
def a(a: AnyRef): Boolean
def a(a: Any): Boolean
}
def t: T = ???
in {
import scala.None // any import will do..
t.a("")
}
// Or, we can get here with ambiguous implicits from the formal parameter
// type of the less specific overload to that of the more specific.
object T {
def foo(a: Any) = true
def foo(a: String) = true
}
in {
import scala.None
implicit def any2str1(a: Any): String = ""
implicit def any2str2(a: Any): String = ""
T.foo("")
}
}
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