Macro config_namespace_with_hashmap 

macro_rules! config_namespace_with_hashmap {
    (
     $(#[doc = $struct_d:tt])*
     $(#[deprecated($($struct_depr:tt)*)])?  // Optional struct-level deprecated attribute
     $vis:vis struct $struct_name:ident {
        $(
        $(#[doc = $d:tt])*
        $(#[deprecated($($field_depr:tt)*)])? // Optional field-level deprecated attribute
        $field_vis:vis $field_name:ident : $field_type:ty, $(transform = $transform:expr,)? default = $default:expr
        )*$(,)*
    }
    ) => { ... };
}