Re: Re: Re: Re: Need a workaround: Class variables with MLDBM::Sync

What happens is Storable can not convert Perl code, which is what this MLDBM::Sync lock object is, into something it can store on disk. I haven't resolved the issue yet. I'm trying to use Data::Dumper, since it can work with Perl code, or, more precisely, it stores objects by converting them to Perl code.

Comment on Re: Re: Re: Re: Need a workaround: Class variables with MLDBM::Sync

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Re(5): Need a workaround: Class variables with MLDBM::Sync by perrin (Chancellor) on Oct 14, 2002 at 16:29 UTC
You're trying to store the MLDBM::Sync object inside of MLDBM::Sync? Don't do that! Here's the sort of thing I had in mind: package Calendar; # constructor sub new { my $class = shift; my %args = @_; my $calendar = {}; my %data; my $sync_dbm_obj = tie(%data, 'MLDBM::Sync', "$args{DIR}\\$arg +s{year}.db", O_CREAT\|O_RDWR, 0640) or die "can't open tie to $args{year}.db: $!"; $calendar->{'data'} = \%data; # if just created, initialize hash with default values if( !$calendar->{data}{months} ) { $sync_dbm_obj->Lock; $calendar->{data}{year} = $args{year}; $calendar->{data}{months} = {}; my $aref = $calendar->{data}{months}; foreach my $month (1..12) { $aref->{$month} = _init_days($calendar->{data}{year}, $mon +th); } $calendar->{data}{months} = $aref; $sync_dbm_obj->UnLock; } return bless $calendar, $class; } [download] When you need access to the MLDBM::Sync object you just say `my $sync_dbm_obj = tied $calendar->{data}` to get it. Of course this is not an OO approach. If you really want to use OO, you should make accessor methods for $calendar->months(), $calendar->year(), etc. instead of just using a tied hash.	[reply] [d/l] [select]

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Re(5): Need a workaround: Class variables with MLDBM::Sync
by perrin (Chancellor) on Oct 14, 2002 at 16:29 UTC

package Calendar;

# constructor
sub new {
    my $class = shift;
    my %args = @_;
    
    my $calendar = {};
    my %data;

    my $sync_dbm_obj = tie(%data, 'MLDBM::Sync', "$args{DIR}\\$arg
+s{year}.db", O_CREAT|O_RDWR, 0640) 
                        or die "can't open tie to $args{year}.db: $!";
    
    $calendar->{'data'} = \%data;

    # if just created, initialize hash with default values
    if( !$calendar->{data}{months} ) {

        $sync_dbm_obj->Lock;

        $calendar->{data}{year} = $args{year};
        $calendar->{data}{months} = {};
        my $aref = $calendar->{data}{months};
        foreach my $month (1..12) {
            $aref->{$month} = _init_days($calendar->{data}{year}, $mon
+th);
        }
        $calendar->{data}{months} = $aref;

        $sync_dbm_obj->UnLock;
    }
    
    return bless $calendar, $class;
}
[download]

my $sync_dbm_obj = tied $calendar->{data}

Of course this is not an OO approach. If you really want to use OO, you should make accessor methods for $calendar->months(), $calendar->year(), etc. instead of just using a tied hash.

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