use std::io::{ErrorKind};

///
/// Possible error conditions from a `try_sync()` call on the scheduler
///
#[derive(Clone, PartialEq, Debug)]
pub enum TrySyncError {
    /// The queue is busy, so the function has not been executed
    Busy
}

impl Into<ErrorKind> for TrySyncError {
    fn into(self) -> ErrorKind {
        match self {
            TrySyncError::Busy => ErrorKind::WouldBlock
        }
    }
}

///
/// Possible error conditions from a `try_sync()` call on the scheduler
///
#[derive( Clone, PartialEq, Debug)]
pub enum TrySyncError {
    /// The queue is busy, so the function has not been executed
    Busy
}

--- 
+++ 
@@ -1,8 +1,18 @@
+use std::io::{ErrorKind};
+
 ///
 /// Possible error conditions from a `try_sync()` call on the scheduler
 ///
-#[derive( Clone, PartialEq, Debug)]
+#[derive(Clone, PartialEq, Debug)]
 pub enum TrySyncError {
     /// The queue is busy, so the function has not been executed
     Busy
 }
+
+impl Into<ErrorKind> for TrySyncError {
+    fn into(self) -> ErrorKind {
+        match self {
+            TrySyncError::Busy => ErrorKind::WouldBlock
+        }
+    }
+}
Add an Into to convert the try_sync error into an io::ErrorKind error
