fix add

src/main.rs

@@ -61,7 +61,7 @@ fn init() -> io::Result<()> {
 }
 
 fn add(id: &String) -> io::Result<()> {
-    let db = DB::new(STORAGE_PATH)?;
+    let mut db = DB::new(STORAGE_PATH)?;
     if db.items.contains(id) {
         // TODO: ask to edit existing in outer function which invoked this one
         return Err(io::Error::new(
@@ -70,6 +70,7 @@ fn add(id: &String) -> io::Result<()> {
         ))
     }
 
+    db.items.insert(id.clone());
     db.dump(STORAGE_PATH)?;
     
     Ok(())