Does Kotlin provide a way to easily diff two objects, recursively? ```foo.bar.baz.x // 5 val copy =...

# getting-started

[Ray Rahke]

Does Kotlin provide a way to easily diff two objects, recursively?

foo.bar.baz.x // 5
val copy = foo
foo.bar.baz.x = 7

diff(copy, foo) // { field: .bar.baz.x, before: 5, after: 7 }

[Arjan van Wieringen]

AFAIK not. It isn’t a very trivial problem. For a previous project I rolled my own. But I guess that with some compiler plugin magic a lot is possible. With reflection you can also get pretty far.

[Joffrey]

In which form would you expect this to happen? What type would diff return?
If you want to diff for debug purposes or in a textual form in general, you could consider serializing to JSON and diffing the JSON as text (there are libraries for this AFAIK)

[Joffrey]

For instance this one might help with the text diff: https://github.com/GitLiveApp/kotlin-diff-utils

[Jacob]

That "copy" only copied the reference so there won't actually be a diff.