flip selections

src/cursor.rs

@@ -51,6 +51,10 @@ impl Cursor {
 		self.tail = self.head;
 	}
 	
+	pub const fn flip(&mut self) {
+		swap(&mut self.head, &mut self.tail);
+	}
+	
 	// TODO: in visual mode, should only clamp head
 	pub fn clamp(&mut self, scroll_position: usize, screen_size: usize) {
 		let max_row = scroll_position + screen_size - 1;