sub settings {
    my $self = shift;
    %AUBBC = ( %AUBBC, @_ );

    if ( exists $AUBBC{ highlight_function } ) {
        $AUBBC{ highlight_function } = \&code_highlight unless check_subroutine( $AUBBC{ highlight_function } );
        $AUBBC{ highlight } = 0;
        }
    settings_prep();