diff --git a/src/lib.rs b/src/lib.rs
index d80f41b..654be25 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -125,6 +125,8 @@
             IResult::Done(rest, t) => {
                 if rest.is_empty() {
                     Ok(t)
+                } else if rest.len() == input.len() { // parsed nothing
+                    Err(format!("failed to parse {}: {:?}", name, rest))
                 } else {
                     Err(format!("failed to parse tokens after {}: {:?}", name, rest))
                 }