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kotlinlang

If I have

```val lens1: Lens&lt;S, A&gt;
val lens2: Lens&lt;S, B&gt;```
how do I apply them one after another to change field `A` then change field `B` and return `S`?

```fun modify(s: S): S {
  return lens1.modify { a.doStuff() } ?? lens2.modify { b.doStuff() }
}```
i.e. I want not to compose them but to sequence them.

Something like this?

<https://github.com/arrow-kt/arrow/pull/2777>

Nice!

I also wonder how this would be done in Haskell. I'm in process of reading the book on optics, didn't see something similar there yet.

My hunch is that this looks like "sequencing in context" and this speaks "Monad", but lenses are not monads, so this hunch must be wrong :slightly_smiling_face:

Still `copy` in this PR looks like haskell's `do` :slightly_smiling_face:

This uses a mutable `var` in the underlying impl and applies the transformations in sequence