1 files changed, 5 insertions, 0 deletions
diff --git a/src/common/mod.rs b/src/common/mod.rs
index d3beadb..e4322d2 100644
--- a/src/common/mod.rs
+++ b/src/common/mod.rs
@@ -14,8 +14,13 @@ pub fn make_io_err(msg: String) -> io::Error {
     io::Error::new(io::ErrorKind::Other, msg)
 }
 
+
+/// Has length trait
 pub trait HasLen {
+    /// Return length
     fn len(&self,) -> usize;
+    
+    /// Returns true iff empty.
     fn is_empty(&self,) -> bool {
         self.len() == 0
     }