Hi there, Is it possible to make alias for String type some how which inherits all the logic from String and then make multiple dispatch by this custom type? For example: alias MyString = String # Pseudocode f(str::String) = str f(str::MyString) = "prefix" * str Thank you.

What you want isn’t an alias but a wrapper struct Mystring<:AbstractString data::String end Then you can define all the methods you need easily.

@Oscar_Smith It is not that easy according to https://github.com/JuliaLang/julia/tree/master/base/strings I really need to redefine just Base.show and inherit the other methods from String. And, how can I find out which methods for String type exist? Not methods(String) for type constructor but me…

If you define indexing and iterating, most other behaviors should come for free (I think). As long as most methods in base use AbstractString (which they should), you’ll get the rest of the behavior for free.

Possibly useful macro: [image] Composition and inheritance: the Julian way General Usage I’ve found the @forward macro from Lazy.jl quite useful for this purpose: https://github.com/MikeInnes/Lazy.jl/blob/76dab7d30863e8375fc96b2444fdb2ead369bf4c/src/macros.jl#L248-L271 Es…

I am curious about the context. You have multiple versions of an object that contain only the String as data and want to dispatch based on the “type” of string. Do you mind explaining a little bit how this pattern comes about? There may be other solutions that avoid writing a wrapper.

@hendri54 I want to make a small handy library for ANSI color support in terminal for my pet-project.

So dynamic dispatch would be fine (performance wise)?

[image] Boo: I really need to redefine just Base.show and inherit the other methods from String . Sounds similar to https://github.com/stevengj/LaTeXStrings.jl/blob/master/src/LaTeXStrings.jl so you might look at how it’s done there.

If you are worried that there may be methods in other code that are defined for String rather than AbstractString and that should work for your type of string, then a wrapper would not work. If you only care about multiple dispatch for new methods that you define, then perhaps traits would be the s…

Multiple dispatch by String alias

New to Julia

AndiMD July 20, 2020, 10:33pm 5

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Multiple dispatch by String alias

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