pub fn next(&mut self) -> Option<()> {
        if self.current_index >= self.entries.len() - 1 {
            // just incrementing one so that entry will give none.
            self.current_index = self.current_index + 1;
            return None;
        }
        self.current_index = self.current_index + 1;
        Some(())
    }
/// next will advance the iterator. throws error if we reach end.
next will advance the iterator. throws error if we reach end.
next will advance the iterator . throws error if we reach end .
pub fn next(&mut self) -> Option<()> {
        if self.current_index >= self.entries.len() - 1 {
            // just incrementing one so that entry will give none.
            self.current_index = self.current_index + 1;
            return None;
        }
        self.current_index = self.current_index + 1;
        Some(())
    }
pub fn next ( & mut self ) -> Option < ( ) > { if self . current_index >= self . entries . len ( ) - 1 { // just incrementing one so that entry will give none. self . current_index = self . current_index + 1 ; return None ; } self . current_index = self . current_index + 1 ; Some ( ( ) ) }
next will advance the iterator.
next will advance the iterator .
&mut self