diff --git a/src/annotated.rs b/src/annotated.rs
index 9a0e07e..bff85d3 100644
--- a/src/annotated.rs
+++ b/src/annotated.rs
@@ -1,6 +1,6 @@
 use std::marker::PhantomData;
 
-use crate::{ParseResult, Parser};
+use crate::{representation::Representation, ParseResult, Parser};
 
 pub struct AnnotatedParser<P, I, O, E>
 where
@@ -8,6 +8,7 @@ where
 {
     inner: P,
     name: Option<String>,
+    repr: Option<Representation>,
     phantom: PhantomData<(I, O, E)>,
 }
 
@@ -32,6 +33,7 @@ where
         Self {
             inner,
             name: None,
+            repr: None,
             phantom: PhantomData,
         }
     }
@@ -42,4 +44,11 @@ where
             ..self
         }
     }
+
+    pub fn with_repr(self, repr: Representation) -> Self {
+        Self {
+            repr: Some(repr),
+            ..self
+        }
+    }
 }
diff --git a/src/lib.rs b/src/lib.rs
index 681a09f..7aba179 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -5,6 +5,7 @@ mod combinators;
 mod map;
 mod parser;
 mod primitives;
+mod representation;
 mod sequence;
 
 #[cfg(test)]
diff --git a/src/representation.rs b/src/representation.rs
new file mode 100644
index 0000000..dbd06b0
--- /dev/null
+++ b/src/representation.rs
@@ -0,0 +1,2 @@
+#[derive(Debug)]
+pub struct Representation {}