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class TypeAliasVsImplicitTest {
class For[m[_], a](x: m[a]) {
def map[b](y: a => b): m[b] = throw new Error
}
implicit def toFor[m[_], a](x: m[a]): For[m, a] = new For[m, a](x)
trait MyList[A]
def foo(xs: MyList[Int]) = xs.map(x => x) // compiles fine.
type MyListOfInt = MyList[Int]
def bar(xs: MyListOfInt) = xs.map(x => x) // doesn't compile: value map is not a member of TypeAliasVsImplicitTest.this.MyListOfInt
}
// minimal case -- the bug was in type constructor inference where `xs.type` needed to be widened *and* dealiased
// in 2.8.1 implicit conversion search started with a widened type, so that combo never came up
// object Test {
// class For[m[_], a](x: m[a])
// def toFor[m[_], a](x: m[a]): For[m, a] = new For[m, a](x)
//
// trait MyList[A]
// type MyListOfInt = MyList[Int]
//
// val xs: MyListOfInt = error("")
// toFor(xs : xs.type)
// }
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