Can Mirror or other reflection work from the type, not an instance?

I’d like to use reflection to eliminate boilerplate in some SQLite code that I'm writing (for about the 10th time). I see Mirror, but it doesn't look like it does what I want.

Given a type, like this:

struct Foo {
    var id: UUID
    var name: String
    var startDate: Date?
    var amount: Double?
    func bar() { ... }
}

Is it it possible to:

  1. Iterate over those properties without an instance? (Mirror shows me property names if I have an instance.)
  2. See the declared types of the properties? (Mirror just gives me the names and run-time values, it seems.)
  3. See the functions like bar declared in the type?

1 and 2 would help me write something like createTable(for: Foo.self), because I could loop over the properties and decide what SQLite column styles to use.

2 Likes

AFAIK, not, but GitHub - wickwirew/Runtime: A Swift Runtime library for viewing type info, and the dynamic getting and setting of properties. may help

1 Like

Thanks, that library is interesting. I wonder if it depends on non-public binary layouts in a way that could cause apps using the library to break over time.

If my understanding is correct - only if there are breaking changes in Swift ABI. But then your app would need to recompiled.

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