Hello, I am coming from js/ts background. Can someone explain how this code would look like in Julia? Thanks :slight_smile: function sayHello(f: (s: string) => string): string { return f("Hello,"); } sayHello((name: string) => name + "Julia!");

I don’t think you can generally get more specific than Function by default, because the output type and implementation of a function can depend on its input values. However, you can use callable structs to essentially append metadata to a function. Example: struct FunctionWrapper input_types::Ve…

I think the simpler, most direct translation is function sayhello(f::Function) return f("Hello, ") end sayhello(name -> name * "Julia!") The extra typing here isn’t something I’d think too hard about tbh

thank you, this is very educational! :+1:

[image] Satvik: I don’t think you can generally get more specific than Function by default, because the output type and implementation of a function can depend on its input values. To elaborate, this is a fundamental design limitation/feature/tradeoff. A Julia function has many aspects that d…

I do understand the dynamic nature of Julia, but my concern is How do you inform a user that my “function” accepts only arguments of certain types, without comments or additional documentation? In this particular case, sayHello takes not any Function but (s: string) => string But I guess this is …

I can’t say with any certainty if it’s impossible for a dynamically typed language to have a function type that includes input and output types. But it’s definitely not a priority in the mainstream ones, and Julia in particular lacks them by design. In fact, its multiple dispatch completely divorces…

[image] avetissargsian: How do you inform a user that my “function” accepts only arguments of certain types, without comments or additional documentation? A wrapper callable approach seems to be exactly what you’re asking for, putting the argument types and/or the return type into a type sign…

I suggest finding a very different name from FunctionWrapper even though the concept is somewhat the same. CallSignature?

[image] Benny: name The working name is EnforcedTypeSignatureCallables.

That’s a tad long. Wouldn’t mind writing such a package name once in an import, but not a type constructor, I’d rename that so fast. My suggestions were for the type, specifically, but even CallSignature seems a bit long. I just don’t know if it can be shorter without losing clarity. CallTypes?

[image] Benny: That’s a tad long. The package naming guidelines seem pretty clear: Err on the side of clarity, even if clarity seems long-winded to you. RandomMatrices is a less ambiguous name than RndMat or RMT, even though the latter are shorter. On the other hand, it seems like I get…

Specific function type

New to Julia

nsajko July 20, 2024, 6:17pm 18

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Specific function type

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