pub fn all_columns_mut(
        &mut self,
    ) -> impl Iterator<Item = *mut Column> + DoubleEndedIterator + '_ {
        self.columns
            .iter()
            .copied()
            // Skip the sentinel
            .skip(1)
    }
/// Return an iterator over all columns that are in the grid (covered and
/// uncovered).
Return an iterator over all columns that are in the grid (covered and
uncovered).
Return an iterator over all columns that are in the grid ( covered and uncovered ) .
pub fn all_columns_mut(
        &mut self,
    ) -> impl Iterator<Item = *mut Column> + DoubleEndedIterator + '_ {
        self.columns
            .iter()
            .copied()
            // Skip the sentinel
            .skip(1)
    }
pub fn all_columns_mut ( & mut self , ) -> impl Iterator < Item = * mut Column > + DoubleEndedIterator + ' _ { self . columns . iter ( ) . copied ( ) // Skip the sentinel . skip ( 1 ) }
Return an iterator over all columns that are in the grid (covered and
uncovered).
Return an iterator over all columns that are in the grid ( covered and uncovered ) .
&mut self
&mut self