import std; struct Foo(Printable) { int a; } fn usz? Foo.to_format(&self, Formatter* f) @dynamic { return f.printf("Foo[%d]", self.a); } fn int add(int a, int b) @export("adder") { io::printn("In adder"); Foo x = { a }; io::printfn("Print foo: %s", x); return a + b; }