extern crate proc_macro;
use TokenStream;
/// Derive macro for creating opaque types for cxx-cel.
///
/// # Example
///
/// ```ignore
/// #[derive(Opaque, Debug, Clone, PartialEq)]
/// #[cel_cxx(type = "my_app.my_module.MyType")]
/// struct MyType {
/// value: i32,
/// }
/// ```
///