opus refactoring

src/operation.rs

@@ -1,6 +1,10 @@
 use crate::error::DrawerError;
 
 pub trait Operation {
-    fn perform(&self) -> Result<(), DrawerError>;
     fn validate(&self) -> Result<(), DrawerError>;
+    fn execute(&self) -> Result<(), DrawerError>;
+    fn perform(&self) -> Result<(), DrawerError> {
+        self.validate()?;
+        self.execute()
+    }
 }