{
    my $is_refreshing = 0;
    sub refresh_func {
        return if $is_refreshing;
        $is_refreshing = 1;
        # refresh code here
        $is_refreshing = 0;
        return;
    }
}

##</code><code>##

sub refresh_func {
    state $is_refreshing = 0;
    return if $is_refreshing;
    $is_refreshing = 1;
    # refresh code here
    $is_refreshing = 0;
    return;
}