macro_rules! mock_trait {
    ($trait_name:ident $(, $function_name:ident ( $(&self)* $(self)*  $(, $prm_name:ident : $prm_type:ty)* ) $(-> $return_type:ty)*  )* ) => {

        // Do I have an ability to access self or &self token here?

        trait $trait_name{
            $(
                fn $function_name(); // I am gonna put self or &self here
            )*
        }
    }
}

fn main() {
    mock_trait!(
    MyTrait,
    my_function(&self, prm1: &str, prm2: i32) -> &str,
    my_function2(self, prm1: &str,prm2: u64, prm3: i16) -> &str,
    my_function3(self, prm1: &str)
    );
}