Public by default within the package

[mighdoll]

I'd suggest we change the default visibility for elements within the package to be public, and introduce a new keyword 'private' to optionally annotate top level elements. Private elements are visible within the module but not importable by other modules. Private elements cannot be exported outside of the package.

Advantages:

• no annotation effort for tiny projects, everything public is fine.
• importing from wgsl looks just like importing from wesl
• wesl tool implementation will be a bit easier if wgsl code can be interpreted as valid wesl.
• users will have an easier time understanding wesl if any changes to semantics from wgsl come with syntax changes. (i.e. every new wesl feature feels additive, not a change to existing semantics)

(Some counterarguments are listed in Visibility.md.)

(No change to package visibility - elements are not importable from other packages unless they are explicitly mentioned in export or annotated with @export)

[ncthbrt]

While I agree with public by default, I think interfaces/signatures would be neater replacement than a private keyword.

[mighdoll]

While I agree with public by default, I think interfaces/signatures would be neater replacement than a private keyword.

Perhaps a code sample to explain?

[ncthbrt]

I have an example in my PR: https://github.com/ncthbrt/wesl-spec/blob/load-proposal/ModulesInterfaces.md

[ncthbrt]

Copied from the pr:

// A module signature:

mod sig MathImpl {
    const DEG_TO_RAD: f32;
    type Quat; // An opaque type. It's exact representation is hidden from users
    fn quat_from_euler(xyzRad: vec3<T>) -> Quat;
}

// Another module signature
mod sig Pi {
    const PI: f32;
}

// A third module signature
mod sig MainMath {
    // Here Float conforms to both MathImpl and Pi
    mod Float : MathImpl + Pi;
}

mod sig F32 {
    type T: f32;
}

alias MainMathSig = MainMath;

// This can be type checked to determine 
// whether Math (and consequently Float conform to the provided signature)
mod Math -> MainMathSig {
    mod FloatMath {
        alias T = f32;
        const DEG_TO_RAD: f32 = 0.0174533;
        const PI: f32 = 3.142;
        alias Quat = vec4<f32>;

        fn quat_from_euler(xyzRad: vec3<f32>) -> Quat {
            // Implementation here
        }

        fn private_function() -> f32 {
            // Implementation here
        }
    }
    // An alias for a module that is exposed with the following signatures:
    alias Float : MathImpl + Pi + F32 = FloatMath;
}

// Usage
Math::Float::quat_from_euler(vec4<f32>(90.0 * Math::Float::DEG_TO_RAD))

// Not allowed as the FloatMath module isn't in the interface
// Math::FloatMath::quat_from_euler(vec4<f32>(90.0 * Math::Float::DEG_TO_RAD))

// Not allowed as private_function isn't in the interface
// Math::Float::private_function()

[ncthbrt]

We could probably also invent some syntax to do the same thing for an entire file (or do what ocaml does with optional interface files that sit next to the implementation)

[mighdoll]

I'd suggest we:

1. change the spec to say public by default
2. open a new issue for module visibility control (private, or module interfaces, etc.)
3. open a new issue for package visibility/renaming controls (@public, export, or)
4. then close this issue

[ncthbrt]

Happy with that

On Wed, 09 Oct 2024 at 21:19, mighdoll @.***> wrote:

I'd suggest we:

1. change the spec to say public by default
2. open a new issue for module visibility control (private, or module interfaces, etc.)
3. open a new issue for package visibility/renaming controls @.***, export, or)
4. then close this issue

— Reply to this email directly, view it on GitHub https://github.com/wgsl-tooling-wg/wesl-spec/issues/28#issuecomment-2403257580, or unsubscribe https://github.com/notifications/unsubscribe-auth/ACCJEWMCXXQGEN5TPD6CZRDZ2V6TNAVCNFSM6AAAAABOIPBD4SVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDIMBTGI2TONJYGA . You are receiving this because you commented.Message ID: @.***>