diff --git a/pttodoest/src/main.rs b/pttodoest/src/main.rs
index 698d112..486d7bb 100755
--- a/pttodoest/src/main.rs
+++ b/pttodoest/src/main.rs
@@ -204,12 +204,12 @@ impl File {
     ) -> Result<(), String> {
         for before in before.iter() {
             if !after.contains(before) {
-                self.append(Delta::remove_at(before.clone(), now));
+                self.append(Delta::remove_at(before.clone(), now))?;
             }
         }
         for after in after.iter() {
             if !before.contains(after) {
-                self.append(Delta::add_at(after.clone(), now));
+                self.append(Delta::add_at(after.clone(), now))?;
             }
         }
         Ok(())
@@ -485,18 +485,10 @@ impl Delta {
         Self::new(at, Op::Add, task)
     }
 
-    pub fn remove(task: Task) -> Delta {
-        Self::remove_at(task, Self::now_time())
-    }
-
     pub fn remove_at(task: Task, at: u64) -> Delta {
         Self::new(at, Op::Remove, task)
     }
 
-    pub fn now(op: Op, task: Task) -> Delta {
-        Self::new(Self::now_time(), op, task)
-    }
-
     fn now_time() -> u64 {
         std::time::SystemTime::now()
             .duration_since(std::time::UNIX_EPOCH)