use func_trace::trace; func_trace::init_depth_var!(); fn main() { foo(Foo("Foo".to_string())); } #[derive(Debug)] struct Foo(String); #[trace(pretty)] fn foo(a: Foo) -> Foo { a } #[cfg(test)] #[macro_use] mod trace_test; #[cfg(test)] trace_test!(test_pretty, main());