typealias based on enum

Is it possible to use an enum to create different typealiases?

For instance, this works:

enum MyEnum {
    case one
    case two
}

struct MyType {
    let type: MyEnum 
    let name: String
    
    // lots of other stuff
}

typealias One = MyType
let one = One(type: .one, name: "One")

Is it possible to pass type: .one already in the typealias, something like this (but this doesn't compile):

typealias One = MyType(type = .one)
let one = One(name: "One")

Can I do this?

You can't use a type alias since you want a dynamic solution. One way is to make use of the init method instead.

Either by creating a custom init for each use case like

extension MyType {
    init(oneName: String) {
        self.init(type: .one, name: oneName)
    }

    // more init methods
}

let myType = MyType(oneName: "One")

Or you can use an enum where each item represents a way to create an MyType instance.

enum MyTypeCreator {
    case one(name: String)
    // other use cases 
}

extension MyType {
    init(_ creator: MyTypeCreator) {
        switch creator {
        case .one(let name):
            self.init(type: .one, name: name)
        //...
        }
    }
}

let myType = MyType(.one(name: "One"))

Both ways will let you hide any implementation details inside the init and for more control you can make the default init private.