3 files changed, 15 insertions, 3 deletions
diff --git a/src/calendar.rs b/src/calendar.rs
index fcec54e..a46795b 100644
--- a/src/calendar.rs
+++ b/src/calendar.rs
@@ -58,7 +58,7 @@ impl Calendar {
             }
         }
 
-        single.sort_by_key(|k| k.start);
+        single.sort();
         Ok(Calendar { single, periodic })
     }
 
diff --git a/src/date.rs b/src/date.rs
index 8d41c67..45a0c28 100644
--- a/src/date.rs
+++ b/src/date.rs
@@ -9,7 +9,7 @@ use chrono::offset::Utc;
 use chrono_tz::{Tz, UTC};
 
 
-#[derive(Debug, Copy, Clone, PartialEq, PartialOrd, Eq)]
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
 pub enum Date {
     Time(chrono::DateTime<Tz>),
     AllDay(chrono::Date<Tz>),
@@ -109,6 +109,12 @@ impl Ord for Date {
     }
 }
 
+impl PartialOrd for Date {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
 impl Add<Duration> for Date {
     type Output = Date;
 
diff --git a/src/event.rs b/src/event.rs
index e186cfd..2859ff8 100644
--- a/src/event.rs
+++ b/src/event.rs
@@ -8,7 +8,7 @@ use date::Date;
 use errors::EventError;
 
 
-#[derive(Debug, Clone, PartialEq, PartialOrd, Eq)]
+#[derive(Debug, Clone, PartialEq, Eq)]
 pub struct Event {
     pub start: Date,
     pub end: End,
@@ -82,6 +82,12 @@ impl Ord for Event {
     }
 }
 
+impl PartialOrd for Event {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
 impl FromStr for Status {
     type Err = EventError;