macro_rules! destructure_fields{
    ($matched:expr; $($variant:path),+ => $value:ident) => (
        match $matched {
            $($variant($value))|+ => $value
        }
    );
    ($matched:expr; $($variant:path),+ => $($values:ident),+) => (
        destructure_fields!(@create_pattern $matched, $($variant),+ => ($($values),+))
    );
    (@create_tuple ($($values:expr),+)) => {
        $($values)+
    };
    (@create_pattern $matched:expr, $($variant:path),+ => $value_tuple:tt) => (
        match $matched {
            $($variant(destructure_fields!($value_tuple)) => (destructure_fields!($value_tuple))),+
        }
    );
}

enum Test<'a> {
    A(&'a str, usize),
    B(&'a str, usize),
    C(&'a str, usize),
    D(&'a str, usize)
}

impl<'a> Test<'a> {
    fn get_content(&self) -> (&str, usize) {
        destructure_fields!(self; Test::A, Test::B, Test::C, Test::D => string, number)
    }
}

fn main() {
    let (string, number) = Test::B("This is a test!", 5).get_content();
    println!("{}{}", string, number);
}