diff --git a/src/parse.rs b/src/parse.rs
index 39dbfe7..7dac029 100644
--- a/src/parse.rs
+++ b/src/parse.rs
@@ -519,6 +519,11 @@ mod tests {
         parse(include_str!("test/example.fae"));
     }
 
+    #[test]
+    fn clock() {
+        parse(include_str!("test/clock.fae"));
+    }
+
     mod expr {
         use super::*;
 
diff --git a/src/test/clock.fae b/src/test/clock.fae
new file mode 100644
index 0000000..abd48d5
--- /dev/null
+++ b/src/test/clock.fae
@@ -0,0 +1,59 @@
+interface Update {
+    mut fn update(f64) bool;
+    fn display() string;
+}
+
+struct Clock12Hr {
+    bool pm = true,
+    u8 hours = 12,
+    u8 minutes = 0,
+    u8 seconds = 0,
+    f64 sub = 0.0,
+}
+
+impl Clock12Hr {
+    mut fn tick_seconds() {
+        .seconds = .seconds + 1;
+        if .seconds >= 60 {
+            .seconds = 0; 
+            .tick_minutes();
+        }
+    }
+
+    mut fn tick_minutes() {
+        .minutes = .minutes + 1;
+        if .minutes >= 60 {
+            .minutes = 0; 
+            .tick_hours();
+        }
+    }
+
+    mut fn tick_hours() {
+        .hours = .hours + 1;
+        if .hours >= 13 {
+            .hours = 1;
+        } else if hours == 12 {
+            .hours = not .hours;
+        }
+    }
+}
+
+impl Clock12Hr Update {
+    mut fn update(f64 dt) bool {
+        let mut dirty = false;
+
+        .sub = .sub + dt;
+        while .sub > 1.0 {
+            .sub = .sub - 1.0;
+            .tick_seconds();
+            dirty = true;
+        }
+
+        dirty
+    }
+
+    fn display() string {
+        let pm = if .pm { "PM" } else { "AM" };
+        "{}:{}.{} {}".format(.hours, .minutes, .seconds, pm)
+    }
+}