How to access index from the same object

[user753]

I have this object

case class Foo(foo: List[Int], idx: Int)

How can I create lens like this?

modifyLens[Foo](_.foo.index(_.idx))

[adamw]

I'm afraid such constructs are not supported by quicklens - so you'll need to handle this by hand.

[user753]

Thanks. Do you mean like this?

PathLazyModify[Foo, Int]((x, fn) => x.modify(_.foo.index(x.idx)).using(fn))

[adamw]

Yes, exactly! I'll close this issue since you kind of resolved it yourself :)