Shared via Rust Playground

playground.rs

macro_rules! sticky_visibility {
    (@as_item $i:item) => ($i);

    (@parse [$typ:ident] $_cur:tt $members:tt [$($elemname:ident),*] [$($elemtyp:ty),*] { $(,)* }) => {
        sticky_visibility!(@as_item pub struct $typ $members);
        impl $typ { pub fn new($($elemname: $elemtyp),*) -> $typ { $typ { $($elemname: $elemname),* } } }
    };
    (@parse $t_:tt $_cur:tt $members:tt $en_:tt $et_:tt { pub: $($body:tt)* }) => {
        sticky_visibility!(@parse $t_ [pub] $members $en_ $et_ { $($body)* });
    };
    (@parse $t_:tt $_cur:tt $members:tt $en_:tt $et_:tt { priv: $($body:tt)* }) => {
        sticky_visibility!(@parse $t_ [] $members $en_ $et_ { $($body)* });
    };
    (@parse $t_:tt [$($cur:ident)*] { $($members:tt)* } [$($elemname:ident),*] [$($elemtyp:ty),*] { $n:ident: $t:ty, $($body:tt)* }) => {
        sticky_visibility!(@parse $t_ [$($cur)*] { $($members)* $($cur)* $n: $t, } [$($elemname,)* $n] [$($elemtyp,)* $t] { $($body)* });
    };
    (@parse $t_:tt [$($cur:ident)*] { $($members:tt)* } [$($elemname:ident),*] [$($elemtyp:ty),*] { $n:ident: $t:ty }) => {
        sticky_visibility!(@parse $t_ [$($cur)*] { $($members)* $($cur)* $n: $t, } [$($elemname,)* $n] [$($elemtyp,)* $t] { });
    };

    (pub struct $typ:ident { $($body:tt)* }) => {
        sticky_visibility!(@parse [$typ] [] {} [] [] { $($body)* });
    };
}

mod inner {
    sticky_visibility! {
        pub struct Foo {
            pub:
                a: i32,
                b: bool,
            priv:
                c: (i32, bool),
                d: char,
        }
    }
}
use inner::Foo;

fn main() {
    let foo = Foo::new(42, true, (1, false), '\0');
    
    println!("{:?} {:?}", foo.a, foo.b); // ok
    println!("{:?} {:?}", foo.c, foo.d); // error
}