How do I do a typedef in mojo?

Question

I want to implement a class with a property whose type I can change globally at compile time. For example,

let ID_TYPE = Int

@value
struct MyStruct:
    var a: ID_TYPE

However, let seems not to be applicable to define types, as I receive the error invalid call to '__del__': argument #0 cannot be converted from 'Int' to 'Int'mojo

What can I do to avoid having to manually change all places where the ID_TYPE occurs in my code when I change e.g. from Int to Uint8?

Answer 1

Compile-time variables can be set via the alias keyword. Then, the example reads as follows:

alias ID_TYPE = Int

@value
struct MyStruct:
    var a: ID_TYPE