in reply to weird problem or perl-bug?

Heard of autovivification? (btw, its documented in perlref...) 
use strict;
use warnings;
use Data::Dumper;
my @bar;
my $foo = $bar[1]{bar};
die Dumper( \@bar );
__END__
$VAR1 = [
          undef,
          {}
        ];

[download]

MJD says "you can't just make shit up and expect the computer to know what you mean, retardo!"
I run a Win32 PPM repository for perl 5.6.x and 5.8.x -- I take requests (README).
** The third rule of perl club is a statement of fact: pod is sexy.

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Re: Re: weird problem or perl-bug?
by bugsbunny (Scribe) on Dec 20, 2003 at 12:49 UTC
    yep i've heard about it... forgot about it.. have to test... thanx alot
    Does : 
    print 'a' if defined $vars[xxx]{zzz};

    [download]
    brings the element into existense.. i.e. how to check some element w/o turning it into existense if it doesnt exists already ?!
[reply]
[d/l]

      print 'a' if exists $vars[xxx]{zzz};

      [download]
      will check whether the hash contains an element with the key zzz, but not autovivify it. 

      perl -MHTTP::Daemon -MHTTP::Response -MLWP::Simple -e ' ;    # The  
$d = new HTTP::Daemon and fork and getprint $d->url and exit;#spider
($c = $d->accept())->get_request(); $c->send_response( new   #in the
HTTP::Response(200,$_,$_,qq(Just another Perl hacker\n))); ' #  web

      [download]
[reply]
[d/l]
[select]
        So sorry Corion, but wrong ;) 
        use Data::Dumper;
my @vars;
print 'a' if exists $vars[xxx]{zzz};
die Dumper \@vars;
__END__
$VAR1 = [
          {}
        ];

        [download]
        First you check to see if you have a hash, then you check to see if your key exists.

        MJD says "you can't just make shit up and expect the computer to know what you mean, retardo!"
        I run a Win32 PPM repository for perl 5.6.x and 5.8.x -- I take requests (README).
        ** The third rule of perl club is a statement of fact: pod is sexy.

[reply]
[d/l]

In Section Seekers of Perl Wisdom