Is it possible to extend a struct in Rust? [duplicate]

Question

I'm not much into Rust and I look into it when I need to check whether it's possible to do some interesting things using its type system. And I've come up with a question if it's possible to convert the following type definitions written in TS to Rust.

type Data = {
    path: String
    name: String
}

enum Type {
    CSV,
    JPG,
    PNG
}

type CSV = Data & {
    type: Type.CSV
}

type JPG = Data & {
    type: Type.PNG
}

type PNG = Data & {
    type: Type.PNG
}

// To avoid conflicts with the already reserved type File
type MyFile = CSV | PNG | JPG

I've been trying to google something like if it's possible to extend structs in Rust and unfortunately didn't find anything answering my curiosity.

Answer 1

No, it is not possible to extend a struct in Rust.

Trying to do a direct conversion between this Typescript sample and the equivalent Rust wouldn't be idiomatic anyway. You'd probably want to structure it either like this:

enum Kind {
    Csv,
    Jpg,
    Png,
}

struct MyFile {
    kind: Kind,
    path: String,
    name: String,
}

or like this:

struct Data {
    path: String,
    name: String,
}

enum MyFile {
    Csv(Data),
    Jpg(Data),
    Png(Data),
}

depending on your coupling of path/name to the file type.