diff --git a/x/src/lib.rs b/x/src/lib.rs
index fbf5c87..b6d5aed 100644
--- a/x/src/lib.rs
+++ b/x/src/lib.rs
@@ -24,4 +24,10 @@ import!(sub_xpat, xpat, "xpat");
 #[cfg(feature = "macros")]
 pub use sub_macros::{
     FromRepr
-};
\ No newline at end of file
+};
+
+#[cfg(feature = "macros")]
+pub trait FromRepr: Sized {
+    type Repr;
+    fn from_repr(repr: Self::Repr) -> Option<Self>;
+}
\ No newline at end of file