I am implementing a struct MyStruct with a method that should print something in the console. The ideia is the following: I can set a replacement string in MyStruct, for instance MyStruct::set("some", "other"), so that if I execute MyStruct::println("some"), then "other" should show in the console. The main problem is that Rust has no variadic functions. I could probably take a string array instead, but that brings some difficult to read syntax. Any crate or some Rust hidden magic feature that might help with this?
I don't see why you'd need varargs for that?
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What's difficult about an array?
What you write there looks like MyStruct is some kind of hash map or the like. Which Rust already has in its standard library.
I don't see how variadic functions are required for what you have written.
In Rust what looks like variadic functions is created with macros, like println! for example.
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something like the format! macro?
edit: oops, I didnt notice @Zicog already mentioned this in previous comment 
I actually wanted something really close println! macro. So it would be possible to do somenthing like:
MyStruct::println("{} {} {:?}", "some", 1, [1, 2, 3]);
// Should print "other 1 [1, 2, 3]"
Do you want to have a function that accepts a Arguments in std::fmt - Rust ?
No quite. MyStruct should have the feature of replacing some arguments before printing:
MyStruct::set("foo", "bar");
MyStruct::println("{} {} {:?}", "foo", 1, [1, 2, 3]);
// Should print "bar 1 [1, 2, 3]"
Note that not foo, but bar was printed.
You could implement that, but your custom print needs to be a macro to support varargs. It may also not be obvious to the reader what is happening, so be considerate.
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