Change access control (AC) of autosynthesized init to same as AC of declared struct

(this is my first pitch, so please don't be too harsh)


Today (Xcode 11.3.1, Swift 5.1.X) any public struct Foo will get an auto-synthesized initializer (ASI) with access control internal.

This is tedious when working with models/DTOs and multiple packages (modules), where I might wanna initialize a struct from another package, however, its auto-synthesized initializer (ASI) is internal.

It is not possible to simple mark/change the access control of this internal initializer to be public, without implementing it myself. Which quite quickly becomes a bit tedious (especially since Xcode lacks IDE function to generate this initializer for me - exists for classes, but not for struct). This "problem" has some traction on StackOverflow (with comment.)

Two solutions

I see two viable solutions.

Change AC of ASI to match AC of struct

The simplest solution is to just change the default access control of this ASI (auto-synthesized initializer) to match the AC of the declared struct. Meaning no change for internal struct Foo, but would make the ASI of public struct Bar be public.

Introduce syntax to allow for an explicit declaration of AC of ASI

Or we add some new statement (syntax) which would allow me to change the AC of the ASI of a public struct to be public instead of internal. E.g.

public struct Person {
    // some properties
    public let dateOfBirth: Date

    // example of some new statement to make
    // auto-synthesized init public instead of internal
    // similiar to `public private(set) var` syntax.


Where the first solution is the simplest and does not require any new statement/syntax, it might not be what one wants, it might be important to disallow for init of models from other modules/packages. This makes the second solution much more interesting.


This has been discussed many times before, including here

Darn, how silly of me, I confused the two pitches I wanted to do, and did not remember which I already found existing pitches for... thanks for the link!