I think Swift’s defer (https://docs.swift.org/swift-book/documentation/the-swift-pr...) was inspired by/copied from go (https://go.dev/tour/flowcontrol/12), but they may have taken it from an even earlier language that I’m not aware of.

Defer has two advantages over try…finally: firstly, it doesn’t introduce a nesting level.

Secondly, if you write

       foo
       defer revert_foo

A disadvantage is that defer breaks the “statements are logically executed in source code order” convention. I think that’s more than worth it, though.

Yeah, it's especially handy in UI code where you can have asynchronous operations but want to have a clear start/end indication in the UI:

    busy = true
    Task {
        defer { busy = false }
        // do async stuff, possibly throwing exceptions and whatnot
    }