Learning Julia by (ab)using constructor

[rdeits]

Welcome!

@codyit

Is there a more succinct way to define the inner constructor to achieve the same as below code?

You can use @with_kw from Parameters.jl to define your default values like:

@with_kw mutable struct C
  id::String
  speak::Function = (word) -> println(id, word)
end

(I’ve shortened your example a bit, but hopefully the idea makes sense).

@codyit

What’s the meaning of defining variables or functions in the struct (but outside of constructor) scope? Only to be used in inner constructor?

I guess you could use it for that–it’s extremely unusual to define anything inside the struct other than its fields, and I don’t think I’ve ever seen it done in Julia code in the wild. It’s not something I’ve ever needed, particularly because as soon as you start putting your behavior outside of your structs, it doesn’t really make sense.