ErrType should be Debug

src/basic.rs

@@ -8,6 +8,7 @@ pub type OResult = Result<usize, io::Error>;
 
 pub type IResult<'a, O> = Result<(&'a [u8], O), (&'a [u8], ErrType)>;
 
+#[derive(Debug)]
 pub enum ErrType {
     Incomplete(Option<usize>),
     Failed(String),