Exporting extension methods with a fixed receiver

[prolativ]

Compiler version

3.3.4, 3.7.0-RC1-bin-20250116-0f9e502-NIGHTLY

Minimized code

class Foo():
  def x1: Int = 123

object Foo:
  extension (foo: Foo)
    def x2: Int = 123

  implicit class FooOps(foo: Foo):
    def x3: Int = 123

class Bar():
  val foo = Foo()
  export foo.x1
  export foo.x2

object Bar:
  extension (bar: Bar)
    private def fooOps = Foo.FooOps(Foo())
    export fooOps.x3


val xs = Seq(
  Foo().x1,
  Foo().x2,
  Foo().x3,
  Bar().x1,
  Bar().x2,
  Bar().x3
)

Output

[error] /tmp/ExportExtension.scala:14:14
[error] no eligible member x2 at this.foo
[error]   export foo.x2
[error]              ^^
[error] /tmp/ExportExtension.scala:27:3
[error] value x2 is not a member of Bar - did you mean Bar.x1?
[error]   Bar().x2,
[error]   ^^^^^^^^

Expectation

It should be possible to export an extension method applied on a specific receiver.

Though technically this might be considered a lack of a feature rather than a bug, this is a point were extension methods are less useful than implicit classes.

Considerations

Could this work with export foo.* or would extension exports be restricted to explicitly named methods?

[soronpo]

This is not a bug. Lack of feature and currently extension is not considered as a new block scope, so it does not support import nor export.

[prolativ]

To clarify: exports inside extensions are a feature introduced in 3.2.0 but this functionality is still quite limited