Rust: rename TypeRef and *Type to *TypeRepr, ty to type_repr, and expand some abbreviations in generated docs

[redsun82]

We were already renaming the tip of the type reference hierarchy from Type to TypeRef but weren't doing so with all its descendants.

Additionally, the pat and ty abbreviations are now expanded in generated documentation.

[paldepind]

Why do we want to rename *Type to *TypeRef? Why are they type references and not just types?

[redsun82]

Why do we want to rename *Type to *TypeRef? Why are they type references and not just types?

These are all instances of types written in the code (they are AstNodes, they have a location), and especially they can be optional. "Real" types are semantic, unique despite all the different references to them, and also present for terms that don't have a type spelled out in the code, so they really are a different thing from what I changed here.

[redsun82]

so they really are a different thing from what I changed here

(a thing we don't have, yet)

[paldepind]

Thanks for the explanation @redsun82 👍 🙏 . I guess the name "Ref" wasn't immediately intuitive to me, but aside from that it makes sense. It's the distinction between syntax or notation representing a type and the actual type itself.

[redsun82]

Thanks for the explanation @redsun82 👍 🙏 . I guess the name "Ref" wasn't immediately intuitive to me, but aside from that it makes sense. It's the distinction between syntax or notation representing a type and the actual type itself.

we could also opt for using Repr instead of Ref (that's what we do in Swift for example). Do you think that would be clearer?

[paldepind]

we could also opt for using Repr instead of Ref (that's what we do in Swift for example). Do you think that would be clearer?

Yes, subjectively I think that would be better! That also avoids clashes/confusion with the Rust concept of a reference. For instance the current class name RefTypeRef is a bit awkward.

[redsun82]

@paldepind I went with the rename to TypeRepr, I also find it more intuitive. I've also changed all the getTy predicates to more explicit getTypeRepr (which will also cause less confusion when we start to have getType for actual semantic types), and went for a more specific getElementTypeRepr for ArrayTypeRepr.

[paldepind]

Really great changes 🤩