I am a relatively newbie and I am wondering what is the most appropriate Julian way to reuse the code. I don’t want to trigger discussions on topics already discussed a million times. This post simply aims to lay down a clear list of rules to be followed to write good Julia code, and pose a couple…

Depending on what you do, it might matter or it might not. In this case, I don’t see the advantage over a function nationality(a::Person) isnothing(a.nationality) || return a.nationality error("Call the sheriff!") end

Thank you for pointing this out. I went ahead and modified my code and @code_warntype is all blue now :smiley: For my case, it was probably ok. I am competing against Excel, so the bar is pretty low, but still :blush: I feel better now though so thanks again :raised_hands:

I think you should avoid trying to match traditional OOP too much. See if there is a more Julia friendly way of solving the same problem. But of course there are problems where OOP feels natural. So here are some of my tips. I got one approach used in a package called Figurer , which specifically tr…

@ScottPJones , thanks for suggesting this pattern – I think it works well in many cases. Is there a general name for this pattern? It seems like a simple workaround for allowing concrete inheritance using only base Julia.

Helpful piece of code. I added <: supertype($base_type) now the Citizen mutable struct is also a sub type of AbstractPerson

I read almost all of this thread, and I learned quite a bit. But I still fail to see this one important concern addressed: extend X to obtain a new object called Foo; use Foo in exactly the same way I would use X object; re-defining ONLY those methods for which the Foo behaviour differs from the X …

[image] NightMachinary: re-defining ONLY those methods for which the Foo behaviour differs from the X one, which in the actual case are 3 or 4 (while the X object is accepted by hundred of method); That’s the trickiest thing; actually I’d say that it’s generally impossible, but not for lack o…

Exactly. So Julia itself must have some rudimentary support of concrete single inheritance. Is there any technical difficulty in adding this?

No, there is no structural inheritance. That’s what this whole thread is about. Having structural inheritance makes inlining much harder, forces the compiler to chase endless pointer chains by default and makes the size of an given struct possibly indeterminate (possibly preventing SIMD). The point…

Couldn’t you use a macro to do something like @heritable struct MyParentType my_field::SomeOtherType end Which writes the code: abstract type MyParentType end struct ConcreteMyParentType my_field::SomeOtherType end and then write @inherit struct MyChildType <: MyParentType extr…

Composition and inheritance: the Julian way

General Usage

merlin June 29, 2022, 4:14pm 131

This thread is gold. Got to this point and now I understand a lot more about OOP and Julia type dispatch style paradigms (which I like better, now I know why). FWIW I’m not a CS person.

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Composition and inheritance: the Julian way

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